June 29 Severe Weather...
"Thoughts on Severe Weather Outbreak of June 29"
Well the much hyped severe weather day is upon us here in Pennsylvania. The cold front is quite visible on the surface map and even satellite. With the front in the vicinity combined with high shear, high humidity, and moderate instibility thunderstorms should erupt with some of the becoming severe. The most likely axis of severe weather is from east central Pennsylvania on eastward to the PA/NJ border. Yesterday the front was in Ohio and sparked a large bow echo complex of thunderstorms that raced across Pennsylvania. After debating yesterday afternoon I decided to place a moderate risk of western Pennsylvania with a slight risk elswhere. My forecast turned out spot on with the moderate risk reaching my moderate risk definition and even in my slight risk some storm reports and warnings occured. As the bow echo marched eastward the cold front began to slow and as this happened the bow echo weakened rapidly. A few lone cells and rain showers were out ahead of the line and a few of them became severe, for example in Northumberland County near Sunbury. It was interesting to watch the development of the line of thunderstorms yesterday as it was relativel unsuall to get a bow echo marching across the western mountains of Pennsylvania. Today we could have a similar event except there could potentially be more supercells. What is questioning myself today is how much instibility will there be available later today, and will the storms fire ahead and along the front or along the convergence zone in far eastern Pennsylvania. Anyways I will try to get the details out in the sections below. Here is my verification map for yesterday...
"Current Weather Setup"
Interesting setup headed our way, but overall it is pretty typical of a normal summertime cold frontal passage accompanied with severe weather. Currently the cold front is over western Pennsylvania and a prefrontal trough is over eastern Pennsylvania. These two areas will be the focal points for severe weather. Looking at the latest satellite it looks as if the entire state of Pennsylvania excluding a few areas in socked in clouds. But as has been the case for the last three days the clouds will begin to thin and dissapate. Already this is occuring over the southcentral mountains in Fulton, Huntingdon, and Centre Counties. The radar is currently showing what appears to be rain showers moving east in parts of eastcentral Pennsylvania, but nothing is reaching the ground and it is only thick clouds. I still am in question though for if the clouds will inhibit the best chances of severe weather. For temperatures they will get up into at least the low 80s in many areas and potentially reaching the upper 80s depending on how much sun is received in some areas. Dewpoints will rise a little throughout the day after starting in the mid 60s they should rise to near 70 later in the day. Today is a very unsuall day as upper levels of the atmosphere almost look tropical today as PWATs are around 1.7inches in the southeastern parts of Pennsylvania. Shear levels are high today ahead of the front with in the low levels around 30knots, mid levels around 50 knots, and upper levels around 65knots. At times in the stronger thunderstorm updrafts these winds will be pulled down to the surface. Damaging winds do appear to be the primary threat today. But isolated tornadoes cannot be ruled out as EHI values are near 2.5 in eastern Pennsylvania along with some minimal helicity values. The SWEAT index for today reaches a max of 250 in extreme northeastern Pennsylvania. CAPE values for today are minimal, but adequate enough for severe weather, and they are around a max of 2000 j/kg. The LI index around -4. Sharp lapse rates especially in northern Pennsylvania may be enough to overcome the high freezing levels so hail could be a slight threat today. The question that needs answered for today is how much instibility will be available by 2pm.
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0741 AM CDT SUN JUN 29 2008
...EASTERN US...
EARLY VISIBLE SATELLITE IMAGERY SHOWS WIDESPREAD CLOUDS FROM EASTERN
OH INTO NY/PA. THESE CLOUDS WILL LIMIT HEATING AND DESTABILIZATION
THIS MORNING...AND MAY SUPPRESS ACTIVE CONVECTION UNTIL LATER THIS
AFTERNOON IN THOSE AREAS. HOWEVER...BACK EDGE OF CLOUDINESS WILL
MOVE INTO WESTERN NY/PA BY LATE MORNING AND PROVIDE A NARROW ZONE OF
INSTABILITY ALONG THE SURFACE COLD FRONT. THIS AREA WILL LIKELY SEE
FIRST INITIATION OF SEVERE STORMS...WITH ACTIVITY DEVELOPING
SOUTHWARD INTO WV/KY/TN BY EARLY AFTERNOON. THESE STORMS WILL MOVE
EASTWARD THROUGH THE DAY INTO A PROGRESSIVELY MORE UNSTABLE AIRMASS
WHERE DEWPOINTS ARE IN THE 60S AND TEMPERATURES WILL WARM INTO THE
MID/UPPER 80S. MESOSCALE MODELS ALSO SUGGEST THE POTENTIAL FOR A
SECONDARY AREA OF CONVECTIVE DEVELOPMENT THIS AFTERNOON OVER PARTS
OF EASTERN PA/SOUTHERN NY AS WEAK MID LEVEL IMPULSE NOW OVER VA
LIFTS NORTHWARD. FORECAST SOUNDINGS SUGGEST STEEPEST MID LEVEL
LAPSE RATES WILL BE PRESENT FROM MD NORTHWARD...WHERE HAIL IS MORE
LIKELY IN STRONGEST CELLS. OTHERWISE...DEEP LAYER EFFECTIVE AND LOW
LEVEL VERTICAL SHEAR WILL BE SUFFICIENT THROUGHOUT THE EASTERN
STATES FOR ORGANIZED MULTICELL TO SUPERCELL STORMS CAPABLE OF
DAMAGING WINDS AND ISOLATED TORNADOES. PORTIONS OF THE NORTHEAST
AND MID ATLANTIC STATES MAY REQUIRE AN UPGRADE TO MODERATE RISK IN
LATER OUTLOOKS...AS DETAILS OF CLOUD COVER AND DESTABILIZATION
BECOME MORE APPARENT.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
Below I have posted some of the morning model runs being the SREF, NAM, and GFS. The NMM model still is letting me have access to it do to its replacement for monitoring tropical weather in the east Pacific. CAPE values are definitely not as highly progged as they were a few days ago. I imagine that this is due part to the fact of the models picking up on the debris clouds across the region in the morning hours. It is odd this year in how every severe weather chance there always seems to be cloud cover inhibiting some convection development. In years before this is not always the case and make forecasting much easier. The NAM model appears most extreme with instibility indices today and the GFS the least. The SREF offers a compromise of the two models. What I am impressed is with progged EHI values by the GFS model. The atlantic coastal plain near Philadelphia has been seeing sun all morning with temperatures already nearing 80degrees. Combined with a trigger with the prefrontal trough over eastern Pennsylvania I can see how supercells form capable of rotation and weak, isolated tornadoes. Be alert for this threat later today. In any case I plan on posting the latest mesoanalysis soundings when they come in. Stay tuned for more updates throughout the day.
"3z SREF Model Forecast Max Cape Index"
(Sunday afternoon)
"12z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Sunday afternoon)
"0z GFS Model Forecast EHI Values"
(Sunday afternoon)
"My Forecast for Severe Weather"
Well it was a tough decision when making my severe weather map. I decided I would rather play it safe than be sorry so I issued a moderate risk of severe weather for southern Pennsylvania on up through extreme eastern Pennsylvania. I believe in these areas they are under the highest threat to due to higher instibility and the higher chance of rotation with any supercells that do form. I believe two areas of convective development can be expected today. One area along the prefrontal trough axis in eastern Pennsylvania where supercellular development is possible. And the other location along the surface cold front in western Pennsylvania where a squall line with damaging winds could form. Some clearing is moving into western Pennsylvania which may just make it enough instibility for the convection to form. Today easily may not reach moderate risk qualifications on my severe weather map, but the potential is there and that is why I issued it. Today we have all of the threats with wind, hail, tornadoes, and heavy rain. As was the case yesterday extreme, frequent lightning should not be too much of a threat. Stay tuned for more updates throughout the day, and just a note... I do not intend to change my severe map any time today. Keep your NOAA weather radio on and handy today and stay tuned for the latest updates. Awareness is how we save lives.
"My Severe Weather Risk Map"
(Sunday)
"Conclusions on Severe Weather Outbreak"
Well I was planning a special blog for my 50th blog, but instead I missed it. Currently this blog is my 53rd. I must say thankyou to all of those that continue to comment throughout the week as I thoroughly enjoy conversing with those that have a similar interest to the weather, photography, nature, and gardening like I do. I have learned so much in the past 7 months and everyday I learn something new. This year has been quite a year so far and I am hoping for more great blogs to come. Again thankyou for all of the great comments I get each day which all make this blog possible. I will continue to write Pennsylvania weather blogs as far as I can see into the future. As usuall if any questions arise feel free to ask them or if my blog seems a little strangely worded feel free to point it out. Looking ahead to the future I am planning some interesting blogs, but I would love if anyone had any suggestions to some blog topics that cover broader topics such as nature, gardening, of course the weather, and photography. I am looking potentially next week to have a photography blog in which I post my favorite weather pictures I have taken and mention a little about them. I hope others post their favorite weather pictures also. Thanks for a great 50 blogs with 50+ more to come. Have a wonderful day!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 3
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 16
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 5.45inches
Yearly Precipitation- 23.52inches
(Temperature Stats...)
Heat Advisories- 4
Excessive Heat Warnings- 0
90degree days- 5
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Updated: 5:59 PM GMT on June 29, 2008
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June 29 Severe Weather...
"Thoughts on Severe Weather Outbreak of June 29"
Well the much hyped severe weather day is upon us here in Pennsylvania. The cold front is quite visible on the surface map and even satellite. With the front in the vicinity combined with high shear, high humidity, and moderate instibility thunderstorms should erupt with some of the becoming severe. The most likely axis of severe weather is from east central Pennsylvania on eastward to the PA/NJ border. Yesterday the front was in Ohio and sparked a large bow echo complex of thunderstorms that raced across Pennsylvania. After debating yesterday afternoon I decided to place a moderate risk of western Pennsylvania with a slight risk elswhere. My forecast turned out spot on with the moderate risk reaching my moderate risk definition and even in my slight risk some storm reports and warnings occured. As the bow echo marched eastward the cold front began to slow and as this happened the bow echo weakened rapidly. A few lone cells and rain showers were out ahead of the line and a few of them became severe, for example in Northumberland County near Sunbury. It was interesting to watch the development of the line of thunderstorms yesterday as it was relativel unsuall to get a bow echo marching across the western mountains of Pennsylvania. Today we could have a similar event except there could potentially be more supercells. What is questioning myself today is how much instibility will there be available later today, and will the storms fire ahead and along the front or along the convergence zone in far eastern Pennsylvania. Anyways I will try to get the details out in the sections below. Here is my verification map for yesterday...
"Current Weather Setup"
COMING SOON!!!
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0741 AM CDT SUN JUN 29 2008
...EASTERN US...
EARLY VISIBLE SATELLITE IMAGERY SHOWS WIDESPREAD CLOUDS FROM EASTERN
OH INTO NY/PA. THESE CLOUDS WILL LIMIT HEATING AND DESTABILIZATION
THIS MORNING...AND MAY SUPPRESS ACTIVE CONVECTION UNTIL LATER THIS
AFTERNOON IN THOSE AREAS. HOWEVER...BACK EDGE OF CLOUDINESS WILL
MOVE INTO WESTERN NY/PA BY LATE MORNING AND PROVIDE A NARROW ZONE OF
INSTABILITY ALONG THE SURFACE COLD FRONT. THIS AREA WILL LIKELY SEE
FIRST INITIATION OF SEVERE STORMS...WITH ACTIVITY DEVELOPING
SOUTHWARD INTO WV/KY/TN BY EARLY AFTERNOON. THESE STORMS WILL MOVE
EASTWARD THROUGH THE DAY INTO A PROGRESSIVELY MORE UNSTABLE AIRMASS
WHERE DEWPOINTS ARE IN THE 60S AND TEMPERATURES WILL WARM INTO THE
MID/UPPER 80S. MESOSCALE MODELS ALSO SUGGEST THE POTENTIAL FOR A
SECONDARY AREA OF CONVECTIVE DEVELOPMENT THIS AFTERNOON OVER PARTS
OF EASTERN PA/SOUTHERN NY AS WEAK MID LEVEL IMPULSE NOW OVER VA
LIFTS NORTHWARD. FORECAST SOUNDINGS SUGGEST STEEPEST MID LEVEL
LAPSE RATES WILL BE PRESENT FROM MD NORTHWARD...WHERE HAIL IS MORE
LIKELY IN STRONGEST CELLS. OTHERWISE...DEEP LAYER EFFECTIVE AND LOW
LEVEL VERTICAL SHEAR WILL BE SUFFICIENT THROUGHOUT THE EASTERN
STATES FOR ORGANIZED MULTICELL TO SUPERCELL STORMS CAPABLE OF
DAMAGING WINDS AND ISOLATED TORNADOES. PORTIONS OF THE NORTHEAST
AND MID ATLANTIC STATES MAY REQUIRE AN UPGRADE TO MODERATE RISK IN
LATER OUTLOOKS...AS DETAILS OF CLOUD COVER AND DESTABILIZATION
BECOME MORE APPARENT.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
COMING SOON!!!
"3z SREF Model Forecast Max Cape Index"
(Sunday afternoon)
"0z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Sunday afternoon)
"0z GFS Model Forecast EHI Values"
(Sunday afternoon)
"My Forecast for Severe Weather"
COMING SOON!!!
"My Severe Weather Risk Map"
(Sunday)
"Conclusions on Severe Weather Outbreak"
Well I was planning a special blog for my 50th blog, but instead I missed it. Currently this blog is my 53rd. I must say thankyou to all of those that continue to comment throughout the week as I thoroughly enjoy conversing with those that have a similar interest to the weather, photography, nature, and gardening like I do. I have learned so much in the past 7 months and everyday I learn something new. This year has been quite a year so far and I am hoping for more great blogs to come. Again thankyou for all of the great comments I get each day which all make this blog possible. I will continue to write Pennsylvania weather blogs as far as I can see into the future. As usuall if any questions arise feel free to ask them or if my blog seems a little strangely worded feel free to point it out. Looking ahead to the future I am planning some interesting blogs, but I would love if anyone had any suggestions to some blog topics that cover broader topics such as nature, gardening, of course the weather, and photography. I am looking potentially next week to have a photography blog in which I post my favorite weather pictures I have taken and mention a little about them. I hope others post their favorite weather pictures also. Thanks for a great 50 blogs with 50+ more to come. Have a wonderful day!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 3
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 16
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 5.34inches
Yearly Precipitation- 23.41inches
(Temperature Stats...)
Heat Advisories- 4
Excessive Heat Warnings- 0
90degree days- 5
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Updated: 1:02 PM GMT on June 29, 2008
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June 27 Severe Weather...
"Thoughts on Severe Weather Outbreak of June 27"
Well we have another day of severe weather on our hands. For yesterday it was very quiet most of the day. It started off very cloud with some drizzle around especially in southern sections. In fact Johnstown and Bradford had low cloud ceilings around 1000ft until around noon. After noon the sun broke out fully in most areas and temperatures soared into the upper 80s with dewpoints in the mid 60s in most locations. Atmospheric soundings were not too impressive for most of the day with some slight CIN over southeastern sections and modest CAPE in most areas. PWATS though were near an impressive 2inches so there was a definite high moisture content aloft. Later in the day a shortwave enhanced thunderstorms over Ohio. They quickly became severe. Due to low winds aloft they moved at a slow pace and a training thunderstorm event occured with some flooding in Ohio. The thunderstorms also became severe with many reports of wind damage. The thunderstorms then moved into western Pennsylvania as instibility had become much higher with CAPE around 3000 j/kg in western Pennsylvania. By evening the thunderstorms formed a small line in the form of a weak bow echo causing some wind damage in many locations. Johnstown, Pennsylvania recorded a 70mph wind gust. Pittsburgh reported lots of damage in the metro area and Erie reported nickel sized hail near the metro along with some trees down. The line continued to move across central Pennsylvania before weakening near Harrisburg. I received a light thunderstorm with .02inches of rain. Overall yesterday my forecast was pretty spot on with a slight risk. I guess I could have not put a slight risk for southeastern Pennsylvania, but o well you cannot be perfect. Here is my verification map...
"Current Weather Setup"
Pretty simple severe weather setup today. This morning there are some left over sprinkles from last nights thunderstorm complexes which was focused along an outflow boundary. Clouds are scattered about the region thicker in some spots than others. But from what I can tell when looking at the current satellite is that the clouds are thinning out and moving out of the state. Currently near Pittsburgh a MCV is moving through relatively slowly. This feature will continue to move east throughout the day. As hot and humid air develops east of the Appalachians, the MCV will provide a trigger for thunderstorms to develop. Steep lapse rates, low LI index, and high CAPE values near 3000 j/kg will lead to the development of severe thunderstorms. Winds aloft are relatively light though which will make an organized widespread wind damage outbreak hard to come by. But with weak winds aloft and PWATs near 2inches heavy rain and flash flooding may be a threat. Currently dewpoints statewide are around the mid 60s with temperatures already nearing 80degrees in the south. Todays event will be very similiar to what has been happening in northwest Ohio the last couple of days. Stay tuned for more updates throughout the day as the latest soundings come in around 12z.
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0101 AM CDT FRI JUN 27 2008
...N-CENTRAL APPALACHIANS TO MID-ATLANTIC COAST...
TIMING OF LARGE SCALE ASCENT ASSOCIATED WITH MCV...FAVORABLE LOW
LEVEL MOISTURE...AND STRONGEST PORTION OF DIURNAL HEATING CYCLE FOR
WEAK CINH...FAVORS POTENTIAL FOR RELATIVE CONCENTRATION OF STG-SVR
CONVECTION OVER THIS AREA THIS AFTERNOON. MAIN CONCERN WILL BE
DAMAGING GUSTS...WITH ISOLATED SVR HAIL ALSO POSSIBLE. GIVEN
WEAKNESS OF AMBIENT FLOW -- E.G. 20 KT OR LESS BELOW 600 MB IN MOST
AREAS -- MAJOR WIND DAMAGE EVENT APPEARS LESS PROBABLE THAN
AGGREGATION OF MORE LOCALIZED DAMAGING GUST EVENTS. SFC DEWPOINTS
MID 60S TO LOW 70S F OVER LOWER ELEVATIONS WILL CONTRIBUTE TO
MLCAPES UP TO 2500 J/KG...WITH NEARLY UNIDIRECTIONAL
DEEP-TROPOSPHERIC PROFILES SUPPORTING LINEAR/FORWARD-PROPAGATING
CONVECTIVE STRUCTURES.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
The models are in pretty similar agreement to today's forecast. Below is the NAM and SREF models with forecast CAPE, SWEAT, and Helicity. The NMM model seemed to have an initiation problem so I could not post it below. CAPE values look like they will get up to 3000 j/kg in southeastern Pennsylvania. The LI index should remain low and very supportive of the development of strong to severe convection. Shear values are pretty low today with little to no helicity so tornadoes should not be too much of a threat today. The largest threats today are for heavy rain and strong winds. Also the atmosphere is containing some high energy levels today so lightning could be quite intense with some of the storms that form. One inhibiting factor today could be these morning clouds that are around. If they do not dissapate soon then we could have some problems for convection trying to form. Stay tuned for more updates throughout the day.
"3z SREF Model Forecast Max Cape Index"
(Friday afternoon)
"12z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Friday afternoon)
"My Forecast for Severe Weather"
Below is my severe weather map for today and I am looking at a slight risk over eastern Pennsylvania and a isolated chance of western Pennsylvania. The MCV will spark thunderstorms beginning in westcentral Pennsylvania. As they move east they will tap into the warm, moist air in eastern Pennsylvania and become severe most likely. Still a chance exists across western Pennsylvania for an orographic pulse thunderstorm to develop and become severe. The Storm Prediction Center in Norman, Oklahoma is in similiar correspondance with their forecast to mine. For Saturday another severe weather map will be issued around early Saturday morning. Also as usuall a verification map on today's severe weather will be issued tomorrow.
"My Severe Weather Risk Map"
(Friday)
"Conclusions on Severe Weather Outbreak"
For Saturday an approaching front will be headed in the northeast's direction. Saturday high temperatures will soar to 90degrees in southern Pennsylvania. Elsewhere temperatures will be in the mid to upper 80s. Dewpoints across the state should be in the upper 60s to low 70s. It is too far out too see if clouds will inhibit severe thunderstorms, but at this point I would say ample sunshine should be available. The strong cold front is ahead of another upper level trough that will drop temperatures back to seasonal values along with drier air. CAPE values for Saturday are near 3500 j/kg according to the NAM. The GFS is still high though around 3000 j/kg. Looking at any CAP to the environment and there is no CAP that should preclude any convective development. Also the SREF model shows 2000 j/kg over southern Pennsylvania for Saturday. Timing with the front is uncertain at this point, but the closer the front the higher the shear and helicity values are. The uncertainty of the fronts timing kept severe weather chances in for Saturday and Sunday. Also some models show slowing of the front around central Pennsylvania. Sunday looks to be the main show here in central and eastern Pennsylvania, dynamics will be similar to what western Pennsylvania delt with Saturday. Though I am worried about debris cloud from the day before inhibiting severe thunderstorm development. That factor definitely needs to be monitored. All in all it looks like a pretty hefty widespread severe weather outbreak will be headed towards Pennsylvania. More updates will be coming with a new blog each day for Saturday and Sunday highlighting each day's severe weather threat. Have a wonderful Friday!!!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 3
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 15
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 3.53inches
Yearly Precipitation- 21.60inches
(Temperature Stats...)
Heat Advisories- 4
Excessive Heat Warnings- 0
90degree days- 5
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Updated: 4:30 PM GMT on June 27, 2008
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June 26 Isolated Severe Weather
"Thoughts on Severe Weather Outbreak of June 26"
Alrighty well a several day period of chances of severe weather is headed our way all leading up to the potentially major outbreak of severe weather for this coming Saturday and Sunday. For Thursday it will begin with the pattern of unsettled weather with isolated severe weather across Pennsylvania. In the sections below will be further explanations of the setup. For now I would like to recap June 23's severe weather. I was yet again taken by surprise as severe weather was not as widespread as I anticipated. The June 22-23 severe weather days were pretty isolated to scattered about the region. Myself and most weather services including the storm prediction center made some pretty bad forecasts in that time period. I issued a moderate risk for most of the region, but it was not necessary. A slight risk would have been more of a solution. But one thing that I did learn is that CAPE values below 1500 j/kg and unsignificant triggering mechanisms really do limit severe weather potential. For June 23 scattered to numerous thunderstorms formed over Ohio and moved into western Pennsylvania. Many severe thunderstorm warnings were issued for large hail. But overall there were just a scattering of hail reports around penny sized hail. As evening approached the storms weakened over central Pennsylvania as instibility was not too awfully high there. By mid evening thunderstorms moved into the Lower Susquehanna Valley where as usuall has the highest instibility in the state of Pennsylvania. Thunderstorms restrengthened. In Adams County 1.75inch diameter hail was reported along with wind damage. In York County over 1000 people were without power. And in Dauphin and Lebanon Counties wind damage was reported in some areas with trees down. Something interesting to note though is the NWS did not issue warnings in Dauphin and Lebanon County and still yet tree damage occured. In my opinion the storm was quite visible on the reflectivity radar to have strong indications have high winds. But still weather is an inexact science where mistakes are made everyday. Anyway the line of thunderstorms moved into Berks, Chester, Montgomery, and Bucks Counties where some wind damage reports did occur. Below is my verification map with all of the storm reports that occured and all of the warnings that were issued during the event. I was not too pleased with my forecast.
"Current Weather Setup"
Pretty typical summertime setup for some severe pulse thunderstorms. The question remains and this is can we get enough sun. That appears likely as in many areas including mine the sun is already out. The CAP we slowly dissapear today and with rising CAPE levels. Shear levels are pretty low and around 20-30knots which could make for some gusty winds with thunderstorms. Freezing levels are around 12,000ft which could make it possible for some small hail. Helicity values and EHI indices are a little higher than normal so some rotation could be possible with a cell or two. A shortwave over Illinois will push into Ohio later today. Meanwhile a departing MCV is moving east out in the Atlantic after already laying down some weak boundaries. Storms should fire later today, but widespread activity is not expected. Dewpoints are higher than they have been than earlier this week with that severe weather. PWATs are extremely high over eastern Pennsylvania at around 1.9inches. Heavy rain is also a threat today. Overall each day should have an increasing number of storms leading up to the big event on Sunday. Stay tuned for updates throughout the day.
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0733 AM CDT THU JUN 26 2008
...MID MS RIVER VALLEY ACROSS THE SRN/ERN GREAT LAKES...
CONVECTIVELY ENHANCED VORT CENTER NOW OVER CENTRAL IL WILL CONTINUE
SLOWLY EWD TODAY...WHERE LARGE AREA OF MODERATE INSTABILITY SHOULD
DEVELOP OVER THE SRN GREAT LAKES REGION. ASSOCIATED INCREASE IN MID
LEVEL WSWLY FLOW AND ASCENT ARE EXPECTED TO INCREASE THREATS OF
LARGE HAIL/DAMAGING WINDS BY THE EARLY AFTERNOON THUNDERSTORMS
DEVELOP INTO NRN IND/SWRN MI/OH. SCATTERED THUNDERSTORMS ARE ALSO
EXPECTED WITHIN MODEST INSTABILITY INTO THE UPPER OH RIVER VALLEY
INTO WRN PA/NY TODAY...IN WAKE OF MORNING CLOUDS/SHALLOW CONVECTION.
FOCUS FOR ACTIVITY WILL BE DIFFUSE...HOWEVER SUFFICIENT SHEAR
/20-30 KT DEEP LAYER SHEAR/ WILL BE IN PLACE TO MAINTAIN A RISK OF
LARGE HAIL/DAMAGING WINDS ACROSS THIS REGION.
...NEW ENGLAND...
EXTENSIVE AREA OF SHALLOW CONVECTION ASSOCIATED WITH LOW AMPLITUDE
SHORTWAVE TROUGH WILL OVERSPREAD THE REGION EARLY TODAY AND INHIBIT
MUCH IN THE WAY OF DESTABILIZATION. ALTHOUGH RESIDUAL LOW LEVEL
MOISTURE /SURFACE DEW POINTS NEAR 60F/ SHOULD SUPPORT WEAK
INSTABILITY WITH DIURNAL HEATING...OVERALL SEVERE THREAT SHOULD BE
LIMITED TO MARGINAL HAIL/WIND WITH STRONGER STORMS.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
As usual models are having some convective feedback problems. The question with the Thursday event is where will the MCS go and even if there is a MCS. Most models seem to indicate a MCS moving across northern Pennsylvania then moving possibly through central Pennsylvania. The track is a little uncertain. The 18z NAM has brough the MCS a little farther south than earlier runs. And the GFS has the storm moving across northern Pennsylvania. The NMM model does not show a complex at all. The reason so much is dependent on the track of the MCS is where the MCS goes is where there will be much more stable air. CAPE values are though still progged near 2000 j/kg in some areas of Pennsylvania according to the GFS and NAM. The NMM model shows its simulated radar of showing some severe segments of thunderstorms across the region. Looking at shear values they are highest over the northern parts of the state. SWEAT values though are highest over southwestern Pennsylvania where the best instibility appears to be located. EHI values are much higher than normal for northern Pennsylvania nearing 2-3. Across eastcentral Pennsylvania values are also 1-2. So this appears like tornadoes may be an isolated threat. The MCS will also lay down boundaries for where the storms will form as if they will be the triggering mechanisms. Overall I am not impressed with the event and it appears like severe weather should not be too widespread. Clouds will be the main inhibiting factor. It may even turn out that the only severe weather may be associated with the morning MCS. The morning MCS is capable of intense lightning, heavy rain, and isolated damaging winds. Tomorrow morning I will have an update as the MCS will be visible for what its affects are for Thursday. There is even a chance a MCS does not even develop. Stay tuned.
"9z SREF Model Forecast Max Cape Index"
(Thursday afternoon)
"0z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Thursday afternoon)
"0z NMM Model Future Simulated Radar"
(Thursday afternoon)
"My Forecast for Severe Weather"
Below is my severe weather map. I have issued a slight risk of severe weather for much of the state, excluding the northeastern sections. In the northeastern parts I have included a 75% risk of typical thunderstorms which also means a 5% risk of isolated severe weather. The entire state is basically under the gun for some isolated severe weather. Nothing of any organization should be expected also nothing widespread should be anywhere. Damaging winds and large hail are the primary threats with todays convection. But again an isolated tornado cannot be ruled out as helicity values are a little bit higher than normal. But overall shear levels are low and only 20-30knots aloft which is pretty weak and may just make for some brief gusty winds of perhaps 40mph. Cloud cover is over much of the state this morning, but breaks are forming and here north of Harrisburg the sun is out at times. Dewpoints are pretty high, but some dry air aloft is moving in and I expect dewpoints to drop throughout the day. Overall today there is not much of a triggering mechanism except a weak shortwave that is currently over Ohio may spark thunderstorms in western Pennsylvania. The highest threat of severe weather today is over southwestern Pennsylvania. Stay tuned for more updates throughout the day.
"My Severe Weather Risk Map"
(Thursday)
"Conclusions on Severe Weather Outbreak"
Looking ahead we are in a very active period for unsettled weather including severe storms. For Friday CAPE values go over 2000 j/kg in southern Pennsylvania combined with near 90degree heat and near 70degree dewpoints I can see how severe weather could be a threat. There is not really a triggering mechanism. But any pulse thunderstorm that develops could be capable of severe weather. The SPC has the state in a 5% risk of severe weather for Friday with the main severe threat to the west in the midwest and Ohio Valley. For Saturday an approaching front will be headed in the northeast's direction. Saturday high temperatures will soar to 90degrees in southern Pennsylvania. Elsewhere temperatures will be in the mid to upper 80s. Dewpoints across the state should be in the upper 60s to low 70s. It is too far out too see if clouds will inhibit severe thunderstorms, but at this point I would say ample sunshine should be available. The strong cold front is ahead of another upper level trough that will drop temperatures back to seasonal values along with drier air. CAPE values for Saturday are near 3500 j/kg according to the NAM. The GFS is still high though around 3000 j/kg. Looking at any CAP to the environment and there is no CAP that should preclude any convective development. Also the SREF model shows 2000 j/kg over southern Pennsylvania for Saturday. Timing with the front is uncertain at this point, but the closer the front the higher the shear and helicity values are. The SPC is taking the Days 4-8 outlook and highlighting Pennsylvania in the Day 4&5 outlooks. The uncertainty of the fronts timing kept severe weather chances in for Saturday and Sunday. Also some models show slowing of the front around central Pennsylvania. All in all it looks like a pretty hefty widespread severe weather outbreak will be headed towards Pennsylvania. More updates will be coming with a new blog each day for Friday, Saturday, and possibly Sunday highlighting each day's severe weather threat. Have a wonderful Wednesday and Thursday!!!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 3
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 14
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 3.50inches
Yearly Precipitation- 21.57inches
(Temperature Stats...)
Heat Advisories- 4
Excessive Heat Warnings- 0
90degree days- 5
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Updated: 3:36 PM GMT on June 26, 2008
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Severe Weather Outbreak June 23
"Thoughts on Severe Weather Outbreak of June 23"
Good Monday morning!!! Well I want to take time to recap a little from yesterday's severe weather and below is my verification map to see how well my forecast turned out. Well what a bust of a day. Severe weather did not really impact the areas the had the highest severe weather parameters. Now I am not too upset with my forecast as I was going to issue a slight risk for the whole region, but upgraded to a moderate risk due to the isolated tornado threat. What actually happened was pulse thunderstorm like supercells developed in southcentral Pennsylvania where large hail and damaging winds occured. Also in northwest Pennsylvania an isolated severe weather report occured. A CAP occured across much of Pennsylvania. The jet stream's position surpressed much of the activity. Overall my forecast was not too good, but really I was expecting this. The SPC yet again really had a bust of a day too. For today another severe weather threat is upon us in Pennsylvania. Later in the evening though a line of thunderstorms moved across western Pennsylvania into Cambria County sparking a severe thunderstorm warning and a hail report of 1inch in the county. Today I expect more thunderstorms to form than yesterday with most of them very capable of becoming severe with hail being the primary threat. As we saw yesterday hail was quite common with even 3inch diameter hail reported in New Hampshire and over 2inch diameter hail in West Virginia. Tornadoes are a slight threat again today, and yesterday too funnel clouds were reported in parts of New York State. Here is yesterday's verification map...
"Current Weather Setup"
Yesterday the ingredients were there, except for a triggering mechanism. There were three shortwaves or pieces of energy that triggered severe weather in Ohio, Virginia, and New England. All Pennsylvania received was some severe pulse thunderstorms in the southcentral part of the state. Now today things are a little different as there is a large convergence zone over the northeast as areas of shortwaves and upper-levels lows. In this case severe weather will be more widespread over the state of Pennsylvania. Storms will likely fire in two locations today. One in eastern Ohio and western Pennsylvania ahead of the actual cold front. And a second firing zone along the right quadrant of the jet stream entrence which will be found in eastern Pennsylvania. In between these two zones will be just pulse thunderstorms. Severe weather parameters for the day are a little more impressive than yesterday. Bulk shear values are around 50knots and up to 60knots in eastern Pennsylvania. Freezing levels are around 9kft which is prime for large hail development. Also the cold pool aloft will again be focused over the region. Shear levels winds though 0-4kft are low at around 20knots. Today's dewpoints are slightly higher than yesterdays as they are in the mid 60s in many areas. But as we saw yesterday the dewpoints do not really inhibit heavy rain producers. PWATs are several deviations above normal around 1.5inches in eastern Pennsylvania. The PWATs get lower moving west across Pennsylvania. CAPE values today should get around 2000 j/kg at the max heating of the day. Already CIN is noticeably lower than it was yesterday so there is less CAP on the atmosphere. Lapse rates look adequate for severe weather. Storm organization for today looks to be mainly cellular with some multicellular storms. All storms should move in a southwest to northeast direction. The LI index today is around -4 similar to yesterday and the SWEAT index is around 250 and that is centered over western Pennsylvania. So for today several zones or boundaries will be where the storms will fire. Areas not in these zones will most likely stay dry similar to yesterday. Severe weather will not be widespread but more of a scattered variety with concentrated areas of storm reports. Stay tuned for more atmospheric soundings throughout the day.
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0731 AM CDT MON JUN 23 2008
...OH VALLEY/APPALACHIANS TO THE EAST COAST...
PERSISTENT UPPER TROUGH OVER THE GREAT LAKES AND OH/TN VALLEY
REGIONS THIS MORNING IS ALREADY BEGINNING TO ACCELERATE/MOVE
EWD...AND MODELS BRING TROUGH ACROSS THE LOWER LAKES/APPALACHIANS
THIS EVENING. AS HAS BEEN THE CASE THE PAST FEW DAYS...A LARGE AREA
OF SEVERE THUNDERSTORM POTENTIAL WILL DEVELOP AHEAD OF THIS FEATURE
FROM THE CAROLINAS NWD INTO THE UPPER OH RIVER VALLEY/NEW ENGLAND
TODAY. ACTIVITY WILL ONCE AGAIN DEVELOP IN SEVERAL EPISODES AS
HEATING AND DEEP ASCENT/COOLING ALOFT PROVIDE INCREASING INSTABILITY
THROUGH THE AFTERNOON...DESPITE WIDESPREAD AREA OF MOIST
CONVECTION/CLOUDS ALREADY IN PLACE OVER THE REGION. LOW LEVEL FLOW
WILL REMAIN FAIRLY WEAK...ALTHOUGH MODERATE SWLY WINDS ALOFT WILL
SUSTAIN 25-35 KT DEEP LAYER SHEAR. THIS WILL SUPPORT ORGANIZATION
INTO LINES/CLUSTERS AND POSSIBLY A SUPERCELL OR TWO...PRODUCING
LARGE HAIL AND DAMAGING WINDS.
LOW LEVEL SHEAR MAY BE A BIT STRONGER EAST OF SURFACE TROUGH
EXPECTED THIS AFTERNOON OVER WRN NEW ENGLAND/HUDSON RIVER VALLEY
INTO CENTRAL VA...WHERE MORE SLY SURFACE WINDS WILL BE COMMON. THIS
SURFACE TROUGH WILL LIKELY FOCUS A MORE ACTIVE CORRIDOR OF
STRONG/SEVERE THUNDERSTORMS FROM THE NRN CHESAPEAKE REGION INTO WRN
NEW ENGLAND. ANOTHER MORE ACTIVE REGION SHOULD BE ASSOCIATED WITH
ENERGY/SHORTWAVE TROUGH DIGGING ESEWD ALONG BACK SIDE OF BROADER
TROUGH AS IT SPREADS ACROSS THE UPPER OH RIVER VALLEY/CENTRAL
APPALACHIANS. HOWEVER...OVERALL SCENARIO WILL LIKELY BE QUITE MESSY
ONCE AGAIN WITH ISOLATED SEVERE THUNDERSTORMS DEVELOPING WITH WEAK
FOCUS THROUGH THE PERIOD.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
The models have been have many struggles with this entire system the last three days. Yet again they do not agree at all. The NMM model intiation is very poor with it indicating only about a CAPE max of 500 j/kg. But it's simulated radar seems to have a good handle on the pop up thunderstorms do I decided to post it along with the other models below. The SREF which did pretty well yesterday is showing CAPE of 1500 j/kg in southeastern Pennsylvania. But I think that number is a little to low and will be more like 2000 j/kg. The GFS is inbetween the NMM and SREF with about 1000 j/kg over most of the area. The NAM model though is around 1500 j/kg to 2500 j/kg across much of the state of Pennsylvania. As a resolution it looks like a nowcast type of forecast in which it is a wait and see type of game. The short term RUC model though seems to be handling the system perfectly. But it is hard to forecast by the RUC model because it only goes out to 12 hrs. With using the RUC model it is a near term type of forecast with putting all the details together. So for today I took into the forecast mostly surface map analysis with the latest mesoanalysis from the SPC, the latest Skewt T soundings, the NAM/SREF model, and past history of the storm. Yet again today could be another bust day of a forecast as it is very hard to tell where storms will fire up as there is no distinct triggering mechanism. Just about any area could see severe thunderstorms today. I would say the southcentral mountains region would be the most likely area for initial storm development. Below are all of the Monday morning model runs.
"3z SREF Model Forecast Max Cape Index"
(Monday afternoon)
"12z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Monday afternoon)
"0z NMM Model Future Simulated Radar"
(Monday afternoon)
"My Forecast for Severe Weather"
As the piece of energy moves through Ohio it will spark thunderstorms across western and central Pennsylvania today that will gradually move east. Today all of the storms will have a southwest to northeast fashion though. Storms that intially develop in the southern Appalachian mountains in West Virginia and Virginia will move northeast up into eastern Pennsylvania. It appears the northern mountains region will have the least amount of storms making there threat of severe weather only slight. For the rest of the region they are under a moderate risk due to the isolated threat of tornadoes, quite large hail, and some isolated damaging winds. Remember my moderate risks due not have the same meaning as the SPC's moderate risk. My risk levels are usually are step above what the SPC predicts due to the fact that severe weather is more uncommon in Pennsylvania and sometimes people are not aware of the threat. Throughout today I expect most of the state under some type of severe thunderstorm watch as was the case yesterday. Stay tuned for many updates through the day today. Keep your NOAA weather radio on and stay tuned for the latest updates from your local NWS and local News Media.
"My Severe Weather Risk Map"
(Monday)
"Conclusions on Severe Weather Outbreak"
Looking ahead towards the future. This is the last severe weather threat for several days. Now for Tuesday I cannot rule out some hail reports due to the daytime instibility and cold pool aloft. For Wednesday things will quiet down. But potentially for Thursday night an MCS complex from the midwest could move across the state with some nocturnal thunderstorms. MCS usually are capable of some intense lightning and heavy rain. For Friday things will become unsettled with some scattered thunderstorms as the heat and humidity increases ahead of the next cold front. For Saturday severe weather could be a large threat as another strong cold front moves through with a deep upper level trough behind it. The SPC is already talking about the threat in their long term discussion...
A SEVERE WEATHER THREAT WILL LIKELY GRADUALLY
INCREASE/DEVELOP EASTWARD ACROSS THE OHIO VALLEY/NORTHEAST STATES BY
THIS WEEKEND...WITH DAY 6/SATURDAY CURRENTLY SEEMING TO HAVE THE
GREATEST POTENTIAL FOR WIDESPREAD SEVERE TSTMS ACROSS THIS REGION.
Stay tuned for the latest updates throughout the week as we are getting into the heart of severe weather season here in Pennsylvania. Have a wonderful Monday!!!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 3
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 13
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 2.97inches
Yearly Precipitation- 21.04inches
(Temperature Stats...)
Heat Advisories- 4
Excessive Heat Warnings- 0
90degree days- 5
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Updated: 4:10 PM GMT on June 23, 2008
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Severe Weather June 21-23...
"Thoughts on Severe Weather Outbreak of June 21-23"
Good Saturday evening!!! Today I was up in northern Pennsylvania in Lycoming County. I was a little surprised to see all the severe weather warnings in Ohio and western Pennsylvania. And I was even more surprised to see a tornado warning in Crawford County with a tornado actually being reported by trained spotters in the southwest parts of the county. Things seem to be weakening this evening as I figured. Also today there were some pulse thunderstorms across the north and a wind damage report was reported in Susquehanna County with a 60mph gust recorded. Also in western Pennsylvania in Mercer County three reports of damage came in with trees and power lines down. The complex of thunderstorms will continue to move east across the state. It appears the majority of the severe threat has ended along with the expired severe thunderstorm watch. But again cannot rule out an isolated cell within the disorganized line. It will be interesting to watch the progression of the complex to see if it will develop into a nocturnal MCS which can be typical during the summer months. At this point I sort of doubt it though as this is drier air in central and eastern Pennsylvania along with not as strong upper atmosphere dynamics. The primary threat for the rest of Saturday night is heavy rain. Now for Sunday and Monday central and eastern Pennsylvania are under the risk for severe thunderstorms. Alot of questions remain though with this setup as a lot depends on what happens overnight tonight. So since I had a busy day and a questionable forecast, I will wait until tomorrow to update the other sections and come up with severe weather risk maps. Have a wonderful and safe Saturday night!!! Keep your NOAA weather radio on overnight tonight in case of any rogue thunderstorm.
"Current Weather Setup"
Yesterday organized convection formed across southern Michigan down through Ohio and back into Indiana. Severe weather reports were pretty widespread. Embedded in the line of storms were some bow echos, one very strong that moved into western Pennsylvania later in the evening yesterday. It also spawned a tornado in Crawford County. Trained spotters reported the tornado so I am not sure why it is not in the official storm reports. Today yet again severe weather will form, but parameters at not all that terribly high. The SPC though has a pretty heavy worded outlook, so they must be seeing things that us the general public is not authorized to see. Though I must take in note the SPC has a horrible track record this year. The NWS State College is not overally excited about the event. But the surrounding NWS's are talking about the event a little more heavily. I think there will be some forecast busts today. For instince in the Mt. Holly discussion it is already apologizing if they make a bad forecast today. Confidence is very low. But in any case I will try to make the best forecast for what I feel is going to happen. I just checked the 11z analysis across the northeast and some CIN which acts as a CAP is present over southeast Pennsylvania. Yet some 1000 j/kg is present over the same region. So once the CAP is broken storms could begin to fire up in this region. Tornadoes are a threat today and this system has a history of producing tornadoes so remain alert today for any more updates. The SPC has highlighted eastcentral Pennsylvania in a rare 5% risk of tornadoes today. Stay tuned for more updates throughout the day!
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0738 AM CDT SUN JUN 22 2008
...MID MS RIVER VALLEY INTO WRN NEW ENGLAND/MIDDLE ATLANTIC...
IMPULSES ROUNDING THE BASE OF BROAD UPPER TROUGH OVER THE GREAT
LAKES WILL LIKELY SUPPORT SEVERAL ROUNDS OF STRONG/SEVERE
THUNDERSTORMS TODAY FROM THE OH VALLEY INTO THE MID ATLANTIC/NEW
ENGLAND. DEEP SWLY WIND FIELDS AND EFFECTIVE BULK SHEAR OF 25-40 KT
SUGGEST STORMS SHOULD ORGANIZE INTO SEVERAL CLUSTERS/LINE SEGMENTS
WITH A FEW SUPERCELLS POSSIBLE.
ONGOING CONVECTION MOVING INTO ERN NY ATTENDANT TO ASCENT WITH A
LEAD SHORTWAVE TROUGH FORECAST MOVING INTO QUEBEC WILL DELAY
HEATING/DESTABILIZATION IN ITS WAKE EARLY TODAY. HOWEVER...AIR MASS
IS EXPECTED TO DESTABILIZE SUFFICIENTLY AHEAD OF THE ONGOING
ACTIVITY AND SHOULD SUPPORT AN INTENSIFICATION OF TSTMS AS THEY
TRACK ACROSS PARTS OF ERN NY/WRN NEW ENGLAND.
ADDITIONAL DEVELOPMENT IS EXPECTED THROUGH THE DAY ALONG A SURFACE
TROUGH WHICH WILL MOVE S/SEWD TODAY AND SHOULD EXTEND FROM LOWER
MI/THE LOWER GREAT LAKES SWWD TOWARDS THE MID MS RIVER VALLEY THIS
AFTERNOON. DESPITE RELATIVELY WEAK LOW LEVEL WINDS...MODERATE TO
STRONG MID LEVEL FLOW WILL RESULT IN 30-40 KT OF EFFECTIVE SHEAR
SUPPORTING ORGANIZED STORMS INCLUDING LINES AND POSSIBLY A FEW
SUPERCELLS.
LATER THIS AFTERNOON...HEATING AND INFLUX OF GREATER LOW LEVEL
MOISTURE NWD FROM THE MID ATLANTIC REGION WILL ALLOW AXIS OF
MODERATE INSTABILITY TO DEVELOP IN WAKE OF EARLY DAY STORMS INTO
CENTRAL/ERN NY. THIS SHOULD SUPPORT WIDESPREAD THUNDERSTORM
DEVELOPMENT AHEAD OF BROAD UPPER TROUGH AS ASSOCIATED SURFACE
FRONT/TROUGH MOVES EWD INTO THE REGION. LOW LEVEL SHEAR IS EXPECTED
TO BE STRONGER NEAR SURFACE COLD FRONT/TROUGH AND ATTENDANT WEAK
AREAS OF LOW PRESSURE FROM THE MASON-DIXON LINE/CENTRAL PA INTO ERN
NY LATER THIS AFTERNOON...INCREASING THE POTENTIAL FOR SUPERCELLS
AND PERHAPS A TORNADO OR TWO OVER THIS REGION. OTHERWISE...STORMS
WILL ORGANIZE INTO LINES/CLUSTERS WITH THREATS OF LARGE HAIL AND
DAMAGING WINDS INTO THE MID EVENING.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1254 AM CDT SUN JUN 22 2008
...NORTHEAST STATES/MID ATLANTIC COAST...
UPPER TROUGH/SURFACE COLD FRONT WILL CONTINUE TO SHIFT EASTWARD FROM
THE OHIO VALLEY TO THE NORTHEAST STATES/MID ATLANTIC COAST ON
MONDAY. WHILE SOME SCATTERED SHOWERS/TSTMS MAY BE ONGOING IN THE
MORNING...CLOUD BREAKS/DIURNAL HEATING WILL LIKELY LEAD TO SURFACE
BASED DESTABILIZATION AHEAD OF THE COLD FRONT BY LATE MORNING/EARLY
AFTERNOON. WITH 60S F DEWPOINTS AHEAD OF THE FRONT...POTENTIAL WILL
EXIST FOR WEAK TO MODERATE INSTABILITY WITH CORRIDORS OF 1000-1500
J/KG MLCAPE POSSIBLE. BENEATH 40-45 KT SOUTHWESTERLY FLOW IN THE MID
LEVELS...MODERATELY STRONG/LARGELY UNIDIRECTIONAL WIND PROFILES WILL
FAVOR WELL-ORGANIZED MULTICELLS CAPABLE OF SMALL BOWS/DAMAGING
WINDS...WITH COOL TEMPERATURES ALOFT/STEEP LAPSE RATES ALSO FAVORING
A SEVERE HAIL THREAT.
"Day 2 SPC Severe Weather Risks"
"Model Analysis"
Sunday morning model initiation was very poor. The NMM model has a very poor hold on this entire system and I will not be using it for any support. The SREF model seems to have a pretty good grab on this complex situation. Later today it develops CAPEs near 1500 j/kg in eastcentral Pennsylvania and elsewhere CAPEs around 1000 j/kg. The values are marginal at best. Dewpoints today are pretty low but slowly rising thanks to last night's moisture from the thunderstorm line. Currently dewpoints are in the low 60s and possibly they could rise to the upper 60s. Temperatures are going to be higher than originally expected due to full sunshine statewide this morning. But with a weak southwest flow and an incoming trough temperatures should stay in the low 80s to possibly mid 80s. Shear values are modest at best with high winds aloft at 80knots and winds in the low level jet of only 30knots. I have a feeling today could be quite a bust day. The local NWS have been sticking to the models nonstop and this morning they forecasted the whole region to be thick in clouds, which obviously we are not. The EURO model also predicted a coastal low affecting us, which currently we see that it will not affect us. Helicity values are not impressive today along with EHI values at 1 or below. The SWEAT index is around 250 which yet again is not overally impressive. The highest of severe weather parameters are found along the surface cold front that will extend from central Pennsylvania through eastern NY. Also riding along with be weak low pressure systems. But the front will be relatively weak and will not really act as a focus point for organized convection, but it still should aid in isolated convection which has the potential for supercellular development. Tornadoes are a potential threat today from central Pennsylvania on eastward. Across western Pennsylvania orographic lift will give way to ridgetop pulse thunderstorms under the upper-level trough and deep cold pool aloft. Hail is the primary threat under 8kft freezing levels. Collapsing thunderstorm cores could also potentially lead to strong straightline winds, but this threat should be isolated at best. Overall I am not looking at an impressive outbreak. For Monday's severe weather threat I will have another discussion on Monday morning.
"3z SREF Model Forecast Max Cape Index"
(Sunday afternoon)
"12z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Sunday afternoon)
"3z SREF Model Forecast Max Cape Index"
(Monday afternoon)
"12z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Monday afternoon)
"My Forecast for Severe Weather"
So you may be asking since I do not think the outbreak will be too impressive, then why do I have a moderate risk of severe weather outlooked for eastern Pennsylvania. Well remember my maps do not cooridinate for definitions of SPC outlooks. My moderate risk was upgraded from a slight risk due to the tornado threat. Tornadoes are uncommon in Pennsylvania, so I decided to issue a moderate risk due to the uncommon threat faced in PA. I issued a slight risk for western Pennsylvania with a 5% risk of severe thunderstorms in northwestern Pennsylvania. Currently low clouds and fog are inhibiting high instibility. My forecast today does have a higher than usual bust potential due to many uncertainties with today's forecast. Stay tuned for more updates or if the maps needs a modification with my 1:00pm update.
"My Severe Weather Risk Map"
(Sunday)
"Conclusions on Severe Weather Outbreak"
Again I am not looking at an impressive event at all. The triggers for severe weather are just not anywhere to be found other than orographic lift which is found mainly in western Pennsylvania. The SPC is hyping this event a little more than I am talking about organized supercells and bow echos capable of widespread wind damage and a few tornadoes. For Monday the severe weather threat is not overally high once again and should be most organized in the east but still isolated to scattered in the west as the upper level trough continues to move through. And as we have seen with the last trough, they can easily produce strong to severe thunderstorms during the heat of the day. Stay tuned to your NOAA weather radio and updates from the NWS throughout the day. I will try to provide updates throughout the day on the impending situation. Have a wonderful Sunday!!!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 2
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 13
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 2.97inches
Yearly Precipitation- 21.04inches
(Temperature Stats...)
Heat Advisories- 4
Excessive Heat Warnings- 0
90degree days- 5
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Updated: 4:10 PM GMT on June 22, 2008
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A novice gardener's perspective...
It is time to take a break from an entire blog on the weather forecasts for the week. But instead this blog is going to be on my take as a novice vegetable gardener. And yes I could not help myself, as there will be a little paragraph on the short-term weather forecast.
I think weather/photography/gardening all go hand-in-hand. All of us on the site all seem to have similar interests with a main similar interest of the love of weather. Recently due to rising food prices, rising fuel prices, rising temperatures (thanks to global warming) I decided to really start my own vegetable garden. Now for the past two years before I had just taken a little plot to plant some bean seeds. The faired very well with a bountiful crop each year. I guess I could call myself the bean expert after several years of growing them dealing with problems such as hailstones that destroyed half of the crop. But this year I had an idea that developed of a large vegetable garden. Vegetable gardens have an endless list of advantages that come out of them. Helping the environment, eating healthier due to organic foods, and saving a little bit on food costs are just to name a few of the advantages. Many of the avid readers of my blog are full fledge gardeners whom I consider experts and if I need help I ask them. But I wanted a blog to provide my perspective on vegetable gardening this year. So in this blog I will talk about some of the methods I used so far this year to have a bountiful vegetable and fruit crop. Keep in mind this is my first year and I probably am doing a lot of things wrong, lol. So let me start off in the early spring.
Spring Onions- Coming from a family with a love of onions I just had to grow the ever-popular scallions. I bought a pack of bulbs with about 50 in them and put them in the ground in mid-late March. No I did not prepare the ground, but just took an empty plot on the side of my house where no perennials come up in the late spring. I put the bulbs several inches down in the half-frozen soil. And by the end of March I was lucky enough to see all of the bulbs have come up. Only to be followed by an inch of snow in late March, the onions still faired well and continued to grow. What surprised me most about onions is how long it takes for them to get ready to pick. Them seemed to sprout very quickly but I took a while for them to become large enough to pick and eat. Once they were ready I picked about 10 a week for a while and they tasted wonderful. Next year I plan to plant even more!
Lettuce- I only planted a measly 5 lettuce plants all of the same variety. The survived pretty well threw some of the cold spells in early May. I did get plenty of lettuce crops that always filled for a big bowl of salad to go along with dinner. The lettuce I planted had a slight bitter taste but overall it was wonderful. Next year I want to plant more different varieties of lettuce. Even this fall I want to plant some more lettuce.
Blueberry Bush- I was so excited to get blueberry bushes. I had to buy two so they could cross-pollinate and make a large bountiful crop. By the end of May the bushes had grown much larger and had gotten lots of flowers. The flowers then turn into the blueberries by the end of June. But a lot of the flowers fell off before they had a chance to get into the berries. Now here in Mid June the berries are ripening and getting ready for picking in a week or two. It looks like there are about 25 berries to pick. O well, I did some research and the first year with blueberry bushes usually produce the smallest crop. I cannot wait to next year. But I might have to transplant them, as they are getting a little tight next to the other plants.
First Round of Peas- I planted two packs of pea seeds in my older garden. I also put in about 6 stakes to lets the peas wrap around them as they grow on vines. But for some reason I think I planted the seeds to close together and most of the plant is now dying from bottom to top. Still though there are flowers on the plant, but still no peas to be seen.
Tomato- Well I decided back in March I wanted to expand my vegetable garden with two larger plots of land. I did some research and found that raised bed gardens seem to work very well. I then built two 6ft x 2ft boxes with ten-inch walls. I then filled the boxes with several mixtures of soils including peat moss, hummus, manure, woods soil, and garden soil. In total I had to buy 21 bags of soil which keep in mind was quite costly. But next year I will not have to do this again so it was pretty much a once in done thing. Also forgot to add I put a weed control, but yet water seeping mat at the bottom of the boxes. A few days I later I went out to the local nursery and bought two Roma tomato plants. They first grew extremely slowly, but now they are really taking off. In total I have about 26 tomatoes continuing to grow and there are still more flowers ready to yield more tomatoes.
Herbs- I decided to plant three herb plants that I would use the most. I planted the basil next to the tomato plants and then a garlic chive and parsley plants located below the basil plant. At first the herbs were doing great, but then the long cold spell in May hit and my basil plant, well, died. In June I continue to pick herbs almost every day to spice up some of our dinners. The parsley plant grows like wild and has a bush like appeal. The chive plant is like an ornamental grass type plant and grows a little more slowly than the parsley. The chives do have a wonderful flavor though. As I was putting in a large new shade garden I was putting stepping stones for a pathway and I want to have steppable plants in between a few of the stepping stones. But instead of buying the expensive steppable plants, I decided to buy some herb plants. I bought one oregano plant and two thyme plants. I have yet to pick these though as herbs due to their slow growth in the shade, which was expected.
Zucchini- Well I decided put in some zucchini plants due to they taste great on the grill. The plants were very small when I bought them and only around 3inches tall. I bought four of them. But then shortly they grew like wild and before I knew it they were spilling out over the raised bed boxes. Then they grew flowers and before I knew it there were small zucchinis growing. Now I think I have counted 18 zucchini with I believe more to come. I guess I will be giving a lot away.
Radish- If you’re looking for an easy plant to grow, these are it. They grew like hotcakes and I planted more than I knew what to do with. I gave many radishes away and still I have more cutup in my refrigerator. I pulled the rest of the radishes out when they looked liked they were not growing anymore and moved two cucumber plants in their spot.
Cucumber- Well these plants have been a plague in my side. I planted two in the beginning but then they died right away from the crazy cold spell mentioned earlier in May. Then for a while I did not get anymore. But then I decided to pick up two more cucumber plants at the local nursery and placed them where the radishes were. So far they are very slow to grow and only about 8inches tall. I do have the plant staked. My neighbor's cucumber plant though is growing huge into a large vine.
Carrot- I planted three rows of carrot seeds spaced enough for room to grow. One thing I noticed is these carrots are taking an awful long time to grow, but now they are quite tall. I pulled on yesterday to see how it was coming along and from what I can tell the carrot by the root is beginning to grow too. Carrots are one of my favorite vegetables. I cannot wait to pick some of them.
Second Round of Peas- After a disastrous round with the first pea plants I decided to try to grow them again in my new vegetable garden. I planted three rows of seeds and again placed two stakes in each row. The seeds sprouted quickly and now there are tons of peas on the plant. This pea plant is doing much better than my original and I should have quite a bit of peas for picking, too many to count. I think with the first plant that the peas were just to crowded to give way for growing.
Bean- I am not too big of a fan of beans, but anyway I decided to grow them figuring I would give some of them away like years before. I planted the bean seeds in the new garden and like usual they sprouted quickly. But one thing different from other years is the bean plants are quite taller than years before. Currently there are many small beans growing and will be reading for picking shortly.
Watermelon- In my old, but still used other vegetable garden I had some room after the lettuce plants died from the heat wave to put some watermelon plants which I grew from seeds. It is taking a while for a lot of growth with the plants, but now they seem to be getting larger each day.
Pepper- Last night I was looking at the vegetable garden and one thing was missing. It was pepper plants. So I ran out to the nursery and bought two bell pepper plants to fill in an area in the old vegetable garden. The plants seem healthy and I added a stake to each plant for support.
I must say I am proud of my little vegetable garden. It surely is quite large and bountiful for the little bit of plants I have. I look forward to waking up each day to see what plants might have grown from the night before. I use my rain barrel to water the vegetables every day, which seems to keep the plants even healthier. So far I have no problems with pests, which I am pleased with. I wrote up this blog to share the experiences I have had with my first year of vegetable gardening and I recommend everyone to have a little one as it is easy and fun to watch the plants grow. Below I will post some pictures of my vegetable garden. Have a wonderful day!!! But first my short term forecast.
Short term forecast (Friday)Updated- Sorry for the late forecast discussion. For Friday looks pretty quiet across the state of Pennsylvania as an upper level trough slowly departs from the region. For the morning hours patchy fog could be an issue in some of the favored locales, but overall visibility should not be too low and only around 5miles. A weak shortwave will rotate acround the mainstream of the trough and will provide a few rain showers in northwestern Pennsylvania and over the rest of the region only provide clouds. But a weak upper level low in southern Ohio combined with low convective temperatures may spark a few thunderstorms across southern Pennsylvania today. Any storms are capable of gusty winds and small hail. An isolated storm may approach severe limits. Highs will be slightly warming and into the upper 60s to upper 70s across the state with cloudy intervals throughout the day. Winds will be 5-10mph out of the WNW becoming calm by dusk. Looking ahead real quick appears some shower/thunderstorm chances are ahead with slight risks of severe weather Saturday through Monday. I will have more on that in a new blog probably coming out late Saturday. For now have a wonderful Friday!!!
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Updated: 3:04 PM GMT on June 20, 2008
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Florida weather pictures...
"Thoughts on Severe Weather Outbreak of June 16"
Well Hello!!! I am back from my wonderful trip to central Florida. Instead of listing my latest thoughts on the next severe weather outbreak, I will recap some of my afternoon points. I will leave the sections below for forecasting the severe weather outbreak. Again thanks for all of the daily weather observations, and it seems like I missed a busy weather week across the state. Though my area seemed to get spared all of the significant weather and left with only .11inches of rain. My vegetable garden looks amazing though and really grew while I was gone. I have almost two handfulls of small zuchinni still growing. I picked the rest of my radishes this morning and moved my cucumber plants where the radishes were because the cucumber plants were overcrowded in their original spots. It appears as if blueberries are developing along my blueberry bushes, and my pea and bean plants have many flowers soon to become vegetables. Also my herb plants are doing great. And my watermelon seeds have come up and are about 3-4inches tall. I have decided to put in two pepper plants where the lettuce plants were, as the lettuce plants did not withstand the heat and I decided to dig them out. I sure got quite alot of lettuce though over the spring, so they were definitely worthwile. My tomato plants have tons of small tomatoes that are now growing larger. Now onto weather news of my trip. Two reasons I love the weather is that it is always changing and there is always something new to learn. I saw some very interesting weather events, including a rotating severe thunderstorm. It was about evening and I was tired from the afternoon and decided to sit on the hotel balcony. I heard loud thunder in the distance along with interesting gust front cloud formations. I decided to head inside and turned on the local central Florida news to see what was going on. At that point only a severe thunderstorm warning was out for my area. Then I went back outside and watched the storm with some of the loudest thunder I have ever heard. Also the rain came down in tropical downpoors and even the brand new hotel I was in began to see water filter in under the doors in the six story lobby, which I was shocked to see. But anyway as the storm came to an end I noticed interesting clouds off in the distance to my south. The storm moved from northwest to southeast. I snapped a picture and then another. Upon further examination I noticed a possible funnel cloud off in the distance. Quickly I went back inside to see if there were any updates on the news, and just at that moment a tornado warning was issued for my area, and further south. I will post the pictures maybe later today. Also on my flight trip down to Florida I got some great cumulus and cirrus cloud pictures with the morning sunrise. Then on the flight home we hit the cold front coming through with some thunderstorms nearby. I saw a great lightning show from the plane window, but got no pictures. Our plane flew higher up than normal to avoid the convection. Other than some minor turbulence and some babies crying the flight went fine. There were some interesting notes about Florida though. It is a beautiful state, I have been there several times before, but what I noticed is the build up of so many single homes and condos. Many area forests were now contruction zones, which really bothered me. If any one was curious gas prizes are pretty much the same as they area here in Pennsylvania. So overall my trip was great, but I am happy to be home. I see there was a tornado in Venango County along with severe weather reports in almost every region of Pennsylvania. My county though reported no thunderstorms the entire week. Hopefully today I will have more sections updated, but for now I have some yardwork to do. Have a great Sunday!!!
"Current Weather Setup"
We have quite an interesting setup for severe weather. An upper level low riding along a weakly defined cold front moving south through the Great Lakes region. Meanwhile ahead of the cold front is a lee trough sitting in central Pennsylvania. Two areas of development look to be expected with storm development along the cold front in northwest Pennsylvania, and storm development along the lee trough. Currently this morning two weak complexes of rapidly weakening MCS are moving north and south of the state of Pennsylvania. Cloud cover is pretty sporadic across Pennsylvania. Sunshine is now out for about all regions. Dewpoint levels are rising, but yet not ideal for severe weather. But the upper levels are pretty moist this morning with PWATs near 1.1inches and slowly rising across central Pennsylvania and on eastward. Currently this morning there is also some CAP across the region with some higher CIN being indicated, but that should be diminishing as the day progresses. CAPE max values today I am not overly impressed with as values max out around 2000 j/kg in southeastern Pennsylvania. But here is what I am thinking. The models greatly overestimated cloud cover this morning with would intern inhibit high instibility. But since the sun is out for almost all regions except the Poconos, this would lead me to believe CAPE values to be higher than originally progged by the computer models. I expect CAPEs to possibly reach 2500 j/kg in the Lower Susquehanna and Delaware Valleys. The LI index is pretty low at around -8 near the Delaware Coastal Plain near Philadelphia. Freezing levels are very impressive for Mid June standards with them between 8000-10,000ft. Microbursts will be quite capable of large hail across Pennsylvania. Shear levels are very high as winds from the surface and aloft do not contain the same directions. Winds in this type of situation are frequent to contain gusts up to 70mph+ in the strongest of downdrafts. The lifting mechanism is also there today as the temperature contrasts between the two fronts is quite remarkable. Helicity and EHI values are relatively low today so I am not going to really mention the tornado threat all to much. There just not seem to be enough natural spin in the atmosphere. But as always tornadoes cannot be ruled out. Finally the combined severe weather index, SWEAT, is at over 350 in southcentral Pennsylvania. Typically when the SWEAT is over 300, supercellular development is possible. Along the lee trough is where bow echos and supercells can be expected. Back along the cold front looks to be more of a squall line. Stay tuned for more updates as the latest atmospheric soundings come in throughout the day.
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0743 AM CDT MON JUN 16 2008
...OH VLY INTO MID ATLANTIC STATES/NEW ENGLAND...
60+ KT MID LVL SPEED MAX AND ASSOCIATED LOBE OF ASCENT NOW OVER THE
MID/UPR MS VLY SHOULD REACH IND/OH THIS AFTN...BEFORE CONTINUING
E/SE TO THE DELMARVA REGION TONIGHT.
MODERATE LOW LVL MOISTURE WILL CONTINUE TO SPREAD NEWD AHEAD OF
AFOREMENTIONED COLD FRONT TODAY...WHILE CLOSER TO THE CST...
SOMEWHAT GREATER MOISTURE EXPECTED TO CONTINUE SPREADING N AHEAD OF
LEE TROUGH. AT THE SAME TIME...UNSEASONABLY COOL TEMPS WILL PREVAIL
AT MID LVLS...WITH 500 MB READINGS AOB MINUS 12C AS FAR S AS THE
VA/NC BORDER. WITH THIS SETUP...SFC HEATING SHOULD YIELD MODERATE
INSTABILITY FROM SRN OH/KY/WV E/NE INTO SRN NEW ENGLAND...WITH
SBCAPE AOA 1500 J/KG.
COMBINATION OF INCREASING INSTABILITY WITH DEEP...LARGELY
UNIDIRECTIONAL CYCLONIC FLOW...AND INCREASING UVV WITH APPROACHING
JET STREAK WILL CREATE ENVIRONMENT FAVORABLE FOR NUMEROUS STRONG TO
SVR STORMS BY EARLY AFTN. THESE LIKELY WILL ORGANIZE INTO SEVERAL
CLUSTERS AND BANDS ALONG AND AHEAD OF COLD FRONT AND LEE TROUGH.
EMBEDDED SUPERCELLS AND ASSOCIATED BOWING SEGMENTS LIKELY WILL
PRODUCE FAIRLY LONG SWATHS OF DMGG WIND GIVEN SIZABLE BOUNDARY LYR
TEMP-DEWPOINT SPREADS/STEEP LOW LVL LAPSE RATES...AND STRENGTH OF
MEAN FLOW.
THE STRONGEST STORMS LIKELY WILL HAVE MOVED OFFSHORE AND/OR WEAKENED
BY MID TO LATE EVENING.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
Models are in pretty good agreement with the playout of this event. But there are some strange features they are showing. For example the NMM simulated radar shows no storm development along the lee trough, but yet on the main cold front. Then it has the storms die out before they get east of the mountains. I do not think that will be our scenerio. In terms of severe weather indices they are in pretty good agreement, though I think they are underestimating the amount of surface CAPE that can be expected. Already values at 12z were reported near 1500 j/kg in the southern parts of Pennsylvania. Below are model runs for several severe weather indices from the morning 0z and 9z runs. Stay tuned for more updates on atmospheric soundings throughout the rest of the afternoon.
"9z SREF Model Forecast Max Cape Index"
(Monday afternoon)
"0z NMM Model Forecast Simulated Future Radar"
(Monday afternoon)
"12z NAM Model Forecast SWEAT, Helicity, and CAPE indices"
(Monday afternoon)
"My Forecast for Severe Weather"
So far I am pleased with my severe weather map. As usual after the severe weather event I will post a verification map. My map is in similar correspondance and agreement with the Storm Prediction Center in Norman, Oklahoma's outlook which has a moderate risk out for central and eastern Pennsylvania, with a slight risk for the western third of Pennsylvania. Hail and damaging winds appear to be the primary threats, but an isolated tornado cannot be ruled out due to the high shear levels across the region. Hail parameters show max levels near 2inches in the strongest of updrafts and keep in mind freezing levels in the atmosphere are near 9,000ft and as low as 8,000ft in the northern parts of Pennsylvania. Also keep in mind the winds at the surface are relatively light, but fast aloft so flash flooding could be a threat in the thunderstorms that develop ahead of the front. I think the area most at threat for severe weather is in the Lower Susquehanna Valley corridor up through the Upper Susquehanna Valley corridor. Stay tuned for more nowcast updates throughout the day.
"My Severe Weather Risk Map"
"Conclusions on Severe Weather Outbreak"
This could be a pretty widespread severe weather outbreak across Pennsylvania. What appears to be lacking is the low instibility due to potential cloud cover and the lower than adequate for severe weather, dewpoint levels. But I do think due to the convection not really forming in Ohio this evening, that cloud cover will not be as widespread as originally thought. From what I see wind damage could be pretty widespread. The SPC even has central Pennsylvania in a hatched area which means there is an additional 10% risk of significant severe weather within 25miles of any point. That was the forecast from the SPC from their day 2 12z outlook. I expect a moderate risk to be issued for central and eastern Pennsylvania from the SPC day 1 forecast that comes out early Monday morning. I will get all the updates out during Monday morning for the forecast for the day and I will monitor radar trends to provide short term updates. Also my severe weather outlook map will be issued Monday morning. Please stay alert to rapidly changing conditions tomorrow across all of the state of Pennsylvania. Keep your NOAA weather radio on and stay tuned to of course your NWS and my blog for continuing updates. Looking ahead to next week it looks as if temperatures significantly drop off to the low 70s and upper 60s for high temperatures as a steep trough moves in from the western United States. But by the weekend the trough appears to slowly move off allowing more normal temperatures to filter in. As for severe weather I believe June 16 is the last chance at an organized severe weather event for possibly a week or so. Stay tuned Monday for more updates. Have a great Sunday evening and happy father's day!!!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 2
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 12
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 2.79inches
Yearly Precipitation- 20.86inches
(Temperature Stats...)
Heat Advisories- 4
Excessive Heat Warnings- 0
90degree days- 5
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Updated: 2:15 PM GMT on June 17, 2008
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Observation blog June 6-15...
"Current Temperature"
"Current Dewpoint"
"Current Surface Map and Weekly History of Jet Stream Position"
"Regional Radar"
"Regional Satellite"
"Regional Advisories"
"Soil Moisture Anomalies and 5-day Precipitation Amounts from Hydro Prediction Center"
"Severe Weather Outlooks from Storm Prediction Center Days 1, 2, and 3"
"12hr Estimated Precipitation"
"Forecast Max Temperatures"
"Forecast Min Temperature"
"Forecast Weather at 2pm"
"Current Storm Reports"
"Fire Outlooks from Storm Prediction Center Days 1, 2, and 3"
(All maps courtesy of NOAA and Penn State Meteo.)
"Forecast Model Links"
-NAM model 12z...Link
-GFS model 12z...Link
-NMM model 12z...Link
-SREF model 9z...Link
"Severe Weather Links"
-Atmospheric Soundings Skewt T charts...Link
-SPC Mesoscale Analysis Pages...Link
-Public Spotter Reports for State College NWS...Link
-Severe Weather Model Forecast indices...Link
-Severe Weather Parameter Definitions...Link
"Flooding Links"
-Automated Pennsylvania Rainfall Recording Stations...Link
-Flash Flooding Guidance...Link
-HPC Forecasts for Excessive Rainfall...Link
-Hydrology Predictions for Lakes, Rivers, and Streams...Link
I will be away from June 8-15. This is an observation blog where there are automatically updating maps. Feel free to leave comments below and daily observations are welcomed. Back to regular blogging a few days after I return. Have a wonderful week!!!
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Updated: 9:34 PM GMT on December 27, 2011
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Spotty severe weather across Pennsylvania today...
"Thoughts on Severe Weather Outbreak of June 5"
Well we have been in such an active pattern of severe weather lately, but yet nothing has been too widespread. It is now time to recap the events again. For Tuesday there was a relatively high risk for severe weather in western Pennsylvania and even the Storm Prediction Center in Norman, Oklahoma out looked them in a moderate risk clipping extreme western Pennsylvania. I then issued a moderate risk for western Pennsylvania thinking like everyone else that a MCS will move through overnight. Well what happened is energy was stolen from western Pennsylvania and given back towards Ohio and Indiana where large areas of training super cells formed later tracking southward of Pennsylvania. So for Tuesday I was not too happy at all with my forecast. But for Wednesday my forecast turned out spot on. I issued a slight risk of severe weather for southern Pennsylvania, mostly the border counties. Later that day it turned out a tornado watch was issued for the border counties and even a few severe thunderstorms warnings were issued. But the worst of the weather like I thought moved south of the state hitting our nation's capital with damaging straight-line winds and nearby tornadoes. There was also a report of severe weather in Pennsylvania with .75inch hail being reported in Washington County in western Pennsylvania. Most of the worst of the severe weather stayed south of the state sparing us the worst of the powerful bow echo that moved across Maryland and Virginia with widespread damage. The bow echo was quite impressive. Later by Wednesday evening super cells formed again in the same area in Maryland and Virginia with more wind, hail, and tornadoes being reported. I must say it has been quite an active year for tornadoes across Maryland and Virginia this year. Here is my severe weather verification map for Wednesday June 4...
"Current Weather Setup"
The current weather setup is much simpler than it has been in the past for severe weather particularly this year. What we have is what most people call summer time thunderstorms. But to put that more in meteorological terms, the name of the thunderstorms is pulse thunderstorms. A pulse thunderstorm is a storm that moves at a slow pace that builds over the source of heat and lifts and then collapses as it moves away from the source. The sources typically are from bay breezes, lake breezes, orographic lift, and backdoor cold fronts. Pulse thunderstorms are known for flash flooding, wind damage, and hail. Very common throughout the summer orographic lift gives way to pulse thunderstorms in the Laural Highlands region. So anyway for tomorrow the warm front will have lifted north of Pennsylvania and already moved into New York State. Sunshine will be out along with rising temperatures with dew points in the 70s. High temperatures could approach 90degress in the typical hotspots of York County and Philadelphia County. A very weak backdoor cold front will be located across western Pennsylvania and may be just enough trigger for widespread pulse thunderstorms. Most of the state is under the threat for storms. PWATS will continue to be several deviations above normal so flash flooding will be a threat. Winds aloft are not too strong but yet again now too weak. Unsettled weather will continue with the threat of showers and thunderstorms across the Laural Highlands from Thursday through Monday. But Thursday will be the highest threat of severe weather and widespread storms. Helicity values are pretty minimal but just enough for some possible light rotation in a few convection cells. Freezing levels will be pretty high at around 14,000ft. But pulse thunderstorms can have some very high echo tops near 40,000ft so stronger updrafts may be capable of pulling down some hail. CAPE levels tomorrow are over 2500 j/kg in western Pennsylvania. But a CAP could be an inhibiting factor as warm aloft will be very prevalent. But I expect the CAP to be overcome by afternoon. Meanwhile across the Midwest a potentially very dangerous situation is headed that way with widespread tornadoes possible. Here in the east it is just more heat, humidity, and haze. Enjoy this early taste of the brutality of summer!!!
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0759 AM CDT THU JUN 05 2008
...UPR OH VLY/NY/NRN PA...
SUSTAINED WAA AND BOUNDARY LAYER MOISTENING SHOULD SUPPORT THE
DEVELOPMENT OF SCTD PERIODIC STORM CLUSTERS INVOF DIFFUSE WARM FRONT
FROM PARTS OF ONTARIO E AND SE INTO UPSTATE NY/PA. ALTHOUGH LARGE
SCALE HEIGHT RISES WILL OCCUR ACROSS REGION ON NRN FRINGE OF SERN
STATES RIDGE...DAYTIME HEATING ALONG WITH TERRAIN INFLUENCES MAYS
SUFFICIENTLY BOOST INSTABILITY/UPLIFT TO POSE A RISK FOR A FEW
STRONG/SVR TSTMS WITH HAIL AND/OR LOCALLY DMGG WINDS.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
Models appear to be having a consensus on the forecast for Thursday. They all deliver some partial clearing statewide across Pennsylvania allowing for warmer temperatures and more instability to occur. CAPE values are very impressive and they are forecasted to be higher than any CAPEs so far this year in Pennsylvania. The SREF shows CAPEs at 2500 j/kg in western Pennsylvania near the backdoor cold front. But the NAM model shows CAPE over 3500 j/kg in central Pennsylvania. Helicity values for Thursday should be moderate levels, mainly over western and central Pennsylvania and should be just strong enough for strong to severe thunderstorms to form across the region with flash flooding being the primary threat. CAP levels are high preventing convection early in the day but that later weakens allowing storms to form. The only real big inhibiting factor is a triggering mechanism. From what I see a weak backdoor cold front will be in western Pennsylvania along with a weak shortwave traveling along it should be enough combined with daytime heating and orographic lift for pulse thunderstorms to form. Pennsylvania has a history of widespread severe weather with pulse thunderstorms. EHI values tomorrow are from 0-2 across the state of Pennsylvania with the highest in western Pennsylvania particularly near the Pittsburgh metro region. Super cellular indices are pretty high for parts of central Pennsylvania so organized pulse thunderstorms cannot be ruled out. Overall it looks like a pretty typical summertime pulse thunderstorm type of day. Stay tuned for model updates throughout the day!!!
"15z SREF Model Forecast Max Cape Index"
(Thursday afternoon)
"12z NMM Model Forecast Simulated Future Radar"
(Thursday afternoon)
"My Forecast for Severe Weather"
Below is my forecast severe weather map and as usual a verification map will be issued after the severe weather event. I think the entire state has at least a 5% risk of severe weather with a 10-15% risk of severe weather in central and western Pennsylvania in my slight risk region with is most of the state. I believe the primary threat will be flash flooding, but also hail, damaging winds, and an isolated weak tornado is possible too. Over the event does not look to be too widespread but CAPE values are pretty impressive so I can not rule out some widespread damage in a few counties that see the worst of the pulse thunderstorms. High temperatures should range from 82-90degree across Pennsylvania with dew points also ranging from 65-70degrees. Morning fog may be an issue, but that should dissipate shortly under the strong June sun inversion. For Thursday night showers and thunderstorms will fizzle out after dusk with mild lows in the 60s with more late night fog. For Friday another slight risk of thunderstorms, but high temperatures should be in the 90s. Warm air aloft will act as a CAP preventing widespread convection. For Saturday through Monday high temperatures will be in the low 90s to mid 90s across the state. An official heat wave is high temperatures over 90 for three days or more and that looks like that is what we are going to happen. So enjoy the heat and humidity. Pulse thunderstorms remain a threat over the weekend, but chances should be around 20% each day.
"My Severe Weather Risk Map"
(Thursday)
"Conclusions on Severe Weather Outbreak"
Well my travels take me down to Florida from June 8-15. I am going to post an observation blog for that week in which will be a blog full of automatically updating maps that will represent all the basic necessary meteorological maps all in one blog. I would appreciate while I am gone for people to leave daily weather reports on what happened that day so when I get back I can tell what happened over the past week. Feel free to comment throughout the week in the observation blog. By the way I am approaching my 50th blog in about 6 blogs, so I will have something special planned for that one. Also my winter recap blog part II, well; I have not even started on it yet. My deadline for that is the end of the month in June. Also if you had not heard May went down across Pennsylvania about 3-5degrees below normal on average for climate reporting stations across the entire state. Also my June outlook may not be coming out this month. Since the end of May through early June is the busiest time of the year for me and I have just not gotten around to working on gathering information for my prediction. But overall what it looks like is above normal precipitation and average to slightly above temperatures. I just also want to say that my May outlook was spot on with below normal temperatures that I predicted and above normal precipitation just like I predicted. Anyway, lol, this is my last written blog before my trip. So everyone have a wonderful upcoming week and enjoy the latest heat and humidity!!!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 0
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 12
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 2.66inches
Yearly Precipitation- 20.73inches
(Temperature Stats...)
Heat Advisories- 0
Excessive Heat Warnings- 0
90degree days- 0
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Updated: 5:57 PM GMT on June 05, 2008
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More Pennsylvania severe weather...
"Thoughts on Severe Weather Outbreak of June 2-3"
Another interesting storm setup is headed our direction with potential for severe weather across almost all regions of Pennsylvania for some point within the next three day. But first off I want to talk about the severe weather from May 31 on Saturday. Many people I know are very curious about what went wrong for not having the widespread severe weather. Well let me start off with forecasts. The Storm Prediction Center in Norman, Oklahoma issued a rare moderate risk for eastern Pennsylvania with a 45% chance of wind damage, 30% chance of severe hail, and even an impressive 10% chance of tornadoes. Then the rest of the state was under a slight risk for severe weather. Overnight Friday severe weather developed across the Ohio Valley with around 20 tornadoes reported. The supercells in that region joined together to form an mesocyclone thunderstorm complex that then pushed its way into western Pennsylvania by around five in the morning. A tornado watch was issued for western Pennsylvania. The MCS slowly moved across Pennsylvania and never ended up weakening. Strong dynamics were available that were near extremely impressive standards. Shear and helocity indices were sky high and EHI values were high too. But yet the MCS threw clouds across the entire region near the system and to the north. This meant anyone north of the Mason-Dixon line in Pennsylvania was socked in cloud cover most of the day. To the south in Maryland and Virginia severe weather broke out with mainly wind damage and hail. But one confirmed tornado and two unconfirmed tornadoes were reported in Maryland. Later in the day the MCS moved south of Pennsylvania allowing sun to break out, especially in the north. Now remember the MCS was located along the warm front. So the cold front followed in later in the day creating two areas of concentrated severe weather mostly located in northern Pennsylvania. An intense line of thunderstorms became very organized over the Poconos and isolated severe thunderstorms occured across northwestern Pennsylvania. Evening was fast approaching and most of the severe weather then dissapated quickly before affecting southern Pennsylvania. Southern Pennsylvania, which had the most impressive storm dynamics, was skipped for severe weather due to the morning MCS complex. Forecasts for every station, NWS, Storm Prediction Center, and myself had made pretty poor forecasts. But overall though I was not too upset as each of my moderate/high risks were under a tornado watch at some point. And across northern Pennsylvania severe weather reports did come in. Overall I give myself a somewhat satisfactory job. Below is my forecast map against the actual storm reports and the actual warnings that went out. Now for more information on the current June 3-4 severe weather see other sections below for more information.
"Current Weather Setup"
Alright another relatively complicated weather setup is headed towards Pennsylvania. Why can it never be plain and simple? O well it is only everchanging weather. Anyway moisture is on the increase across Pennsylvania with PWATS already around 1.4inches in extreme western Pennsylvania. But later tonight 4-5 deviation above normal PWATS will move into the region. The Low-level jet will also focus in moisture souring up from the Gulf of Mexico. The warm front and cold front are going to become stationary across the region as shortwaves and vortexes of precipitation move in across the region. It appears as if there will be three rounds of precipitation. First round will be Tuesday afternoon where thunderstorms are forming across areas of Pennsylvania as instibilities aloft are increasing along with at the surface. CAPE values look to approach 1000 j/kg in southern Pennsylvania today with high helicity values and 850 winds remain around 50+ knots. Freezing levels look to be around 10,000ft so hail remains to be a threat. Later Tuesday night a vortex will move in along the warm front and there will be a MCS along with it. The models are as typical suffering from convective feedback issues, but it appears as if tonight a MCS will develop across northern Illinois and track across Indiana and Ohio before moving into Pennsylvania after midnight. Overnight upper level instibility will remain high and continue to leave the oppurtinity for severe thunderstorms across some areas at the front-end of the MCS. But the MCS will be in a weakening phase. It appears as if heavy rain will be the main threat as mid-level isentrophic lift is high and PWATS are high. Southern Pennsylvania may be able to squeeze out 1inch of rain. By tomorrow morning the MCS will be weakening. Again then we are faced with another tough question. How fast can things clear out? Based on what past history has shown us this year it appears as if clouds look to prevail for the most part. Still it appears though another round of thunderstorms will form in Ohio and track along with stalled front. A few severe thunderstorms may be a threat, but overall dynamics are not there for anything widespread. High temperatures may stay below 80degrees for most areas along with dewpoints in the low 70s. Alot of questions remain for the setup of the MCS Tuesday night and early Wednesday morning and there is a big bust factor. I now want to highlight the past history of this storm.
A cold front began to push into the inner-mountain west region on Sunday and began to drop a low pressure along with it. A warm front then lifted northward and severe thunderstorms broke out with the main threat of large hail and two tornado reports. Hail with the diameter of 4.25inches was reported in parts of the northwestern Great Plains on Sunday. Then the system moved eastsoutheast and more severe weather broke out for Monday with several areas of MCS's. A strong one developed across Kansas and moved into Missouri. That MCS showed even derecho like features. Overall 3 tornadoes were reported along with around 250 severe weather reports mostly hail. So far today there have been several MCS areas with one that moved from Illinois through Indiana and now into Ohio with over 50 reports of severe weather with that impressive bow echo and one tornado report also. More convection is expected to break out later today.
"Current Advisories"
"Current Satellite"
(Courtesy of Penn State Meteorology.)
"Current Surface Map and Weekly History of Jet Stream Position"
"Radar for Western Pennsylvania"
"Radar for Central Pennsylvania"
"Radar for Eastern Pennsylvania"
"Forecasts from Storm Prediction Center"
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0759 AM CDT WED JUN 04 2008
...MID ATLANTIC REGION...
BOUNDARY LAYER MOISTURE IS WELL-ESTABLISHED OVER THE MID ATLANTIC
REGION...S OF STNRY FRONT EXTENDING EWD FROM CNTRL PA TO NEAR NYC.
FARTHER S...A WEAK OUTFLOW BOUNDARY FROM OVERNIGHT STORMS ATTM
EXTENDS FROM N OF CRW ESE TO N OF RIC. SATELLITE DATA SUGGEST THAT
MODERATE TO LOCALLY STRONG HEATING WILL OCCUR OVER WV/VA/MD AND DE.
GIVEN MOISTURE AVAILABILITY AND FAIRLY STEEP MID-LVL LAPSE
RATES...THIS SHOULD YIELD SBCAPE TO AOA 2000 J/KG...WITH SLIGHTLY
GREATER VALUES POSSIBLE NEAR THE I-95 CORRIDOR.
UPSTREAM...MCV NOW OVER SRN IND EXPECTED TO CONTINUE E AT ABOUT 40
KTS...REACHING NRN WV AROUND 18Z. COMBINATION OF MCV-INDUCED
ASCENT...AND UPLIFT ALONG FRONT...OUTFLOW BOUNDARY AND THE HIGHER
TERRAIN...SHOULD RESULT IN FAIRLY WIDESPREAD STORM COVERAGE AS
HEATING DESTABILIZES REGION LATER TODAY.
WIND PROFILES WILL FEATURE 40+ KT DEEP...UNIDIRECTIONAL WLY
FLOW...WITH MINIMAL CLOUD-LAYER SHEAR. THIS SUGGESTS THAT WHILE
SEMI-DISCRETE STORMS/POSSIBLE SUPERCELLS MAY OCCUR...ESPECIALLY
ALONG THE AFOREMENTIONED BOUNDARIES...THE MAIN OVERALL
ORGANIZATIONAL MODE OF THE CONVECTION SHOULD BE FORWARD-PROPAGATING
LINES. EMBEDDED STORMS COULD YIELD DMGG WIND...SVR HAIL AND PERHAPS
A COUPLE TORNADOES THROUGH EARLY EVENING...BEFORE MOST OF THE
ACTIVITY MOVES OFFSHORE/WEAKENS.
IN THE WAKE OF THE ABOVE CONVECTION...ADDITIONAL WAVES OF WEAKER
STORMS MAY PERSIST OVER NRN PARTS OF THE MID ATLANTIC STATES THROUGH
EARLY THURSDAY.
"Tornado Risks"
"Hail Risks"
"Wind Risks"
"Model Analysis"
Well time to look at the models and looks at their agreements and discrepancies. Overall the models are handling our severe weather situation very poorly. The NAM especially is having some major convective feedback issues. The GFS is very modest with instibility. And the ever trustworthy SREF is highest in terms of instibility levels. I am very impressive by CAPE values from the 9z SREF model in which it shows values over 2000 j/kg in southern Pennsylvania. That combined with high max helicity and modest shear values may result in severe weather tomorrow. As I mentioned earlier it looks like three rounds of storms. The first round this evening. Second round after midnight. And third round tomorrow afternoon. This all makes it very difficult to get a good grab on the forecast. It was hard deciding on what model to focus on, but I decided to use the SREF due to its good record. Also it appears the old fashioned method, lol, meteorological surface observations may come in handy tonight, and Wednesday. The SWEAT index from the GFS though is impressive in southcentral Pennsylvania with it at 250. Below are some maps I felt that were necessary and may come in handy. Also forecast PWATS tonight and tomorrow may approach an impressive 2inches in southern Pennsylvania so flash flooding may be a threat. It will be interesting to watch that unfold. Some areas may see in excess of 2inches of rain in some favored upsloping precipitation regions. That winner may be Franklin County which has already picked up possibly 1.5inches according to rainfall estimates and it is only the beginning of this quite long event. Also below is the high resolution NMM model which appears to be handling the situation pretty well and it shows widespread thunderstorms tomorrow. Below in my forecast section I will take about some of the inhibiting factors, though, of the potential severe weather.
"9z SREF Model Forecast Max Cape Index"
(Wednesday afternoon)
"0z GFS Model Forecast Helicity"
(Wednesday morning)
"12z NAM Model Forecast CAPE and SWEAT indices"
(Wednesday afternoon)
"0z NMM Model Forecast Simulated Future Radar"
(Wednesday afternoon)
"My Forecast for Severe Weather"
Alright well here is my forecast for the upcoming severe weather. Alot of uncertainty remains and I believe cloud cover might preclude most chances of severe weather tomorrow. Still I left though a slight risk out for southern Pennsylvania. Isolated tornadoes are a threat for tonight and tomorrow morning when helicity and shear values remain high. EHI values are not too impressive, but they are still pretty high for Pennsylvania standards at around 2 for western Pennsylvania. I believe wind damage is the primary threat along with maybe some hail in the strong storms capable of the most powerful updrafts. Flash flooding also appears to be a pretty big threat at PWATs are an impressive 2inches for southcentral Pennsylvania. That combined with the typical Blue Ridges upsloping effect will lead to heavy rain amounts isolated at almost 3inches in some areas. I was going to issue a rain map, but I just did not have the time today. Anyway overall this does not appear to be that major of a severe weather threat, but still it needs to be monitored for any possible severe weather associated overnight with the MCS that will move through western Pennsylvania then into southern Pennsylvania slowly dying out by mid tomorrow morning. I will not be adding updates throughout the night. But my maps that update automatically should be enough warning along with the radars. Be sure to turn on your NOAA weather radio before you go to bed as these MCS will move in late overnight and may pose some severe weather problems especially for western Pennsylvania. Have a great evening!!!
(Wednesday)
"Conclusions on Severe Weather Outbreak"
It will be interesting to see what happens with the severe weather threat and the MCS threat for Tuesday night and Wednesday. There are some major convective issues with the models today and the plain meteorological maps show me a possible bust with the energy being stolen to our south. But still I will continue with my forecast for the MCS complex to move across Pennsylvania Tuesday night and then for a break with another round and threat for later on the day Wednesday. I also quickly want to explain my severe weather maps. My risk area definitions are very different than that of the Storm Prediction Center's official risk definitions. I make my risks based on our climate and how widespread severe weather has been in our region for the year so far. For example a moderate risk of severe with by the SPC in Oklahoma might not have the same meaning as it would here in Pennsylvania because it is rare here so the impact level to people is risen. My threats are usually one above what they would be from the SPC due to the fact of severe weather is not overally common in Pennsylvania. My 75% risk of regular thunderstorms translates to 10% risk of severe weather. My slight risk of severe weather translates to 20% chance of severe weather. My moderate risk of severe weather translates to 30% of severe weather. And my high risk of severe weather translates to 40% of severe weather. Overall I hope this better explains my severe weather maps that I produce. And once again this June 3-4 severe weather outbreak does not look to impressive other than just some isolated reports, maybe though a little more widespread across western Pennsylvania. Also as usuall verficition forecast maps will be issued to recap the event for June 3 and June 4. Have a great Tuesday evening!!!
"Storm Reports"
"Here north of Harrisburg 2008 statistics"
(Severe Weather Stats...)
Severe Thunderstorm Watches- 0
Severe Thunderstorm Warnings- 1
Tornado Watches- 1
Tornado Warnings- 0
Total Thunderstorms- 12
(Precipitation Stats...)
Flood Watches- 4
Flood Warnings- 3
Monthly Precipitation- 0.42inches
Yearly Precipitation- 18.49inches
(Temperature Stats...)
Heat Advisories- 0
Excessive Heat Warnings- 0
90degree days- 0
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Updated: 3:56 PM GMT on June 04, 2008
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