Average hurricane season foreseen by CSU, NOAA, and TSR

By: Dr. Jeff Masters , 4:45 PM GMT on June 02, 2009

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A near-average Atlantic hurricane season is on tap for 2009, according to the seasonal hurricane forecast issued June 2 by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). The CSU team is calling for 11 named storms, 5 hurricanes, and 2 intense hurricanes, and an Accumulated Cyclone Energy (ACE) 88% of average. Between 1950 - 2000, the average season had 10 named storms, 6 hurricanes, and 2 intense hurricanes. But since 1995, the beginning of an active hurricane period in the Atlantic, we've averaged 15 named storms, 8 hurricanes, and 4 intense hurricanes per year. The new forecast is a step down from their April forecast, which called for 12 named storms, 6 hurricanes, and 2 intense hurricanes. The new forecast calls for a near-average chance of a major hurricane hitting the U.S., both along the East Coast (28% chance, 31% chance is average) and the Gulf Coast (28% chance, 30% chance is average). The Caribbean is also forecast to have an average risk of a major hurricane.

The forecasters cited several reasons for an average season:

1) Sea surface temperature (SST) anomalies in the tropical Atlantic are quite cool. In fact, these SST anomalies are at their coolest level since July 1994. Cooler-than-normal waters provide less heat energy for developing hurricanes. In addition, an anomalously cool tropical Atlantic is typically associated with higher sea level pressure values and stronger-than-normal trade winds, indicating a more stable atmosphere with increased levels of vertical wind shear detrimental for hurricanes. Substantial cooling began in November 2008 (Figure 1), primarily due to a stronger than average Bermuda-Azores High that drove strong trade winds. These strong winds increased the mixing of cool waters to the surface from below, and caused increased evaporational cooling.

2) Hurricane activity in the Atlantic is lowest during El Niño years and highest during La Niña or neutral years. This occurs because El Niño conditions bring higher wind shear over the tropical Atlantic. The CSU team expects the current neutral conditions may transition to El Niño conditions (70% chance) by this year's hurricane season. I discussed the possibility of a El Niño conditions developing this year in a blog posted Friday.


Figure 1. Change in Sea Surface Temperature anomaly between November 2008 and 2009. Most of the Atlantic has cooled significantly, relative to normal, over the past 7 months. Image credit: NOAA/ESRL.

Analogue years
The CSU team picked five previous years when atmospheric and oceanic conditions were similar to what we are seeing this year: neutral to slightly warm ENSO conditions, slightly below-average tropical Atlantic SSTs, and above-average far North Atlantic SSTs during April-May. Those five years were 2002, which featured Hurricane Lili that hit Louisiana as a Category 1 storm; 2001, featuring Category 4 storms Michelle, which hit Cuba, and Iris, which hit Belize; 1965, which had Category 3 Betsy that hit New Orleans; 1960, which had two Category 5 hurricanes, Ethyl and Donna; and 1959, which had Category 3 Hurricane Gracie, which hit South Carolina. The mean activity for these five years was 10 named storms, 6 hurricanes, and 2 intense hurricanes, almost the same as the 2009 CSU forecast.

How accurate are the June forecasts?
The June forecasts by the CSU team have historically offered a skill of 20 - 30% higher than a "no-skill" forecast using climatology (Figure 2). This is a decent amount of skill for a seasonal forecast, and these June forecasts can be useful to businesses such as the insurance industry and oil and gas industry that need to make bets on how active the coming hurricane season will be. This year's June forecast uses the same formula as last year's June forecast, which did quite well predicting the 2008 hurricane season (prediction: 15 named storms, 8 hurricanes, 4 intense hurricanes; observed: 16 named storms, 8 hurricanes, 5 intense hurricanes). An Excel spreadsheet of their forecast skill (expressed as a mathematical correlation coefficient) show values from 0.44 to 0.58 for their June forecasts, which is respectable.


Figure 2. Accuracy of long-range forecasts of Atlantic hurricane season activity performed at Colorado State University (CSU) by Dr. Bill Gray's team (colored squares) and Tropical Storm Risk, Inc. (TSR, colored lines). The skill is measured by the Mean Square Skill Score (MSSS), which looks at the error and squares it, then compares the percent improvement the forecast has over a climatological forecast of 10 named storms, 6 hurricanes, and 2 intense hurricanes. TS=Tropical Storms, H=Hurricanes, IH=Intense Hurricanes, ACE=Accumulated Cyclone Energy, NTC=Net Tropical Cyclone Activity. Image credit: TSR.

NOAA's 2009 hurricane season forecast
The National Oceanic and Atmospheric Administration (NOAA), issued its 2009 Atlantic hurricane season forecast on May 21. NOAA anticipates that an average season it most likely, giving a 50% chance of a near-normal season, 25% chance of an above-normal season, and a 25% chance of a below-normal season. They give a 70% chance that there will be 9 - 14 named storms, 4 - 7 hurricanes, 1 - 3 major hurricanes, and an Accumulated Cyclone Energy (ACE) in the 65% - 130% of normal range. The forecasters cited the following main factors that will influence the coming season:

1) We are in an active period of hurricane activity that began in 1995, thanks to a natural decades-long cycle in hurricane activity called the Atlantic Multidecadal Oscillation (AMO).

2) There will either be an El Niño event or neutral conditions in the Equatorial Eastern Pacific. An El Niño event should act to reduce Atlantic hurricane activity. However, our skill at predicting an Niño in late May/early June is poor, so there is high uncertainty about how active the coming hurricane season will be.

3) Cooler-than-average SSTs are currently present in the eastern tropical Atlantic. These cool SSTs are forecast to persist through into August-September-October (ASO). ASO SSTs in the eastern tropical Atlantic have not been below average since 1997. Cooler SSTs in that region are typically associated with a reduction in Atlantic hurricane activity.

Thus, they expect that even though we are in an active hurricane period, the presence of an El Niño or cool SSTs in the eastern Atlantic could easily suppress activity, making a near-average season the most likely possibility. They note that two promising computer models, the NOAA CFS model and the European Center for Medium-Range Weather Forecasts (ECMWF) Global Climate Model System 3, both forecast the possibility of a below-average hurricane season.

2009 Atlantic hurricane season forecast from Tropical Storm Risk, Inc.
The British private forecasting firm Tropical Storm Risk, Inc. (TSR) has joined the ranks of NOAA and Colorado State University in calling for near-average activity. The latest TSR forecast issued June 4 calls for 10.9 named storms, 5.2 hurricanes, 2.2 intense hurricanes, and an Accumulated Cyclone Energy (ACE) 72% of average. The storm numbers are close to the 50-year average of 10 named storms, 6 hurricanes, and 2 intense hurricanes, and are sharp reduction from their April forecast of 15 named storms, 7.8 hurricanes, and 3.6 intense hurricanes. TSR predicts a 50% chance that this season will be in the bottom 1/3 of years historically, and a 40% chance that U.S. landfalling activity will be in the lowest 1/3 of years historically. TSR gives a 32% chance of a near-normal season, and a 17% chance of a below normal season. TSR rates their skill level as 26% above chance at forecasting the number of named storms, 15% skill for hurricanes, and 19% skill for intense hurricanes.

TSR projects that 3.2 named storms will hit the U.S., with 1.3 of these being hurricanes. The averages from the 1950-2008 climatology are 3.2 named storms and 1.5 hurricanes. Their skill in making these April forecasts for U.S. landfalls is 7 - 18% above chance. In the Lesser Antilles Islands of the Caribbean, TSR projects 0.9 named storms, 0.4 of these being hurricanes. Climatology is 1.1 named storms and 0.5 hurricanes.

TSR cites two main factors for their reduced forecast: a large and unexpected cooling of sea surface temperatures in the tropical Atlantic, and warmer SSTs in the Equatorial Eastern Pacific (which might lead to an El Niño event that will bring high wind shear to the Atlantic). TSR expects faster than than normal trade winds from July - September over the Main Development Region (MDR) for hurricanes over the Atlantic (the region between 10° - 20° N from Central America to Africa, including all of the Caribbean). Trade winds are forecast to be 0.83 meters per second (about 1.7 mph) faster than average in this region, which would create less spin for developing storms, and allow the oceans to cool down, due to increased mixing of cold water from the depths and enhanced evaporational cooling. TSR forecasts that SSTs will cool an additional 0.3°C compared to average over the MDR during hurricane season.

Air France crash
The Air France Flight 447 A330 aircraft that disappeared over the mid-Atlantic Ocean yesterday definitely crossed through a thunderstorm complex near the Equator, according to a detailed meteorological analysis by Tim Vasquez. He concludes that "the A330 would have been flying through significant turbulence and thunderstorm activity for about 75 miles (125 km), lasting about 12 minutes of flight time" but that "complexes identical to this one have probably been crossed hundreds of times over the years by other flights without serious incident". See also the excellent CIMSS satellite blog for more images and analysis of the weather during the flight.

Invest 92
NHC is tracking a storm near the Azores Islands (Invest 92L) that is probably the remnants of the core of an extratropical cyclone that closed off some warm air at the center. The system has developed some heavy thunderstorm activity near its center, making this a hybrid storm. However, with ocean temperatures near 62°F (16°C), this storm has little chance of becoming a named subtropical storm.

Jeff Masters

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Quoting Vortex95:
Its incredible how powerfull yet small andrew was. Being in north east dade we got hurricane force winds but they were not as strong as Wilmas!!! to this day I still find that Amazing. In andrew we had a lot of branches down and tile damage but from wilma at least 6 large trees in my area were topped. I believe Andrew gave us 75-80 mph winds Wilma at peak was around 85-90 and gusting well over 100 mph since it was moving so fast. Although it was a tad bit stronger its gusts were what made it so damaging although andrew was a fast mover as well.
Yep... size does matter!
Hugo was not a Cat 5 (except on Wiki and according to some old timers) -- but it was HUGE. As far away as Charlotte, NC (170 miles from landfall) experienced Cat1 hurricane and gusts over 100 mp
Some of the most profound difficulty from the storm, was the human impact on very poor, very rural areas of inland SC


ADDED: Gives me chills thinking about Flying into Hugo - as Jeff Masters did.
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1161. Patrap
I read that soon after the Release today..and the timeline suggest a cascade of events ,which usually is the case..

Whatever occurred,when the breakup occurred,no one suffered ,at that altitude.
A Cabin break up and sudden decompression would render the most fit unconcious immediately.
Member Since: July 3, 2005 Posts: 426 Comments: 128645
Patrap.......an article today somewhat suggest a time line of events on the crash. It was based on the automatice messages that the airplane was sending. It suggested a 14 minute time frame from the first message to the last message. I had "assumed" that whatever happened was quick..possible 3-4 minutes or maybe that was my hope. Is it possible that the passangers actually had a full 14 minutes of knowing they were going to crash?
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1159. Patrap
Bad Mojo can Occur at any time..if one isnt careful or familiar with the EVent .happening and taking the correct action to survive it.

Date: June 26, 1988
Time: 14:45
Location: Habsheim, France
Operator: Air France
Flight number: 296Q
Route: Basel - Basel
AC type: Airbus A320-111
Aboard: 136 (passengers: 130, crew:6)
Fatalities: 3 (passengers: 3, crew:0)

Summary: The plane was scheduled to perform a series of fly-bys at an air show. The plane was to descend to 100 ft. altitude with landing gear and flaps extended. The automatic go-around protection was inhibited for the maneuver. During the maneuver, the plane descended thru 100 ft. to an altitude of 30 feet and hit trees at the end of the runway. The aircraft was totally destroyed by the successive impacts and violent fire which followed. The pilot allowed the aircraft to descend through 100 ft. at slow speed and maximum angle of attack and was late in applying go-around power. Unfamiliarity of the crew with the landing field and lack of planning for the flyby.

Member Since: July 3, 2005 Posts: 426 Comments: 128645
1158. Ossqss
Quoting Patrap:
Exactly ossgs..if he Nosed over at 400Knts @ 40 Degrees,or Nosed up suddenly..all is moot..

Quickly..


Yep, but it must be very scary as a pilot to know you cannot take control of the plane you are flying. You are at the mercy of a chip that someone else programmed. That is a sad part of technological advancement. When we take people out of the equation, we can lose the vision needed to achieve the goal.

Just my take.
Member Since: June 12, 2005 Posts: 6 Comments: 8186
The new Airbus 330 was a “fly-by-wire” plane, in which signals to move the flaps are sent through electric wires to small motors in the wings rather than through cables or hydraulic tubing. Fly-by-wire systems can automatically conduct maneuvers to prevent an impending crash, but some Airbus jets will not allow a pilot to override the self-protection mechanism
___________________________________

I also saw an story simular to this....and again am amazed that technology, while great would NOT allow a pilot to override ANY system in which one is flying.
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1156. Levi32
Quoting Vortex95:
1140. It was a extremly small system with the most powerful winds (i'm winging it ) 15-20 miles at most away from the center (major hurricane winds.) Although I am surpised 100's didn't die from this unless evacuations went so well more than I am thinking.

when it was in the Atlantic at peak winds Ike bigger or smaller than Andrew?


ZCZC MIATCPAT4 ALL
TTAA00 KNHC DDHHMM
BULLETIN
HURRICANE IKE ADVISORY NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL092008
1100 AM AST FRI SEP 05 2008

...IKE MOVING SLIGHTLY SOUTH OF WEST...

MAXIMUM SUSTAINED WINDS ARE NEAR 120 MPH...195 KM/HR...WITH HIGHER
GUSTS. IKE IS A CATEGORY THREE HURRICANE ON THE SAFFIR-SIMPSON
SCALE. SOME WEAKENING IS FORECAST DURING THE NEXT 24 HOURS BUT IKE
IS EXPECTED TO BE A MAJOR HURRICANE IN A COUPLE OF DAYS.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 35 MILES...55 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 105
MILES...165 KM.


Wind radius was the same when he was a Cat 4 just before this advisory as well.
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1155. Patrap
Exactly Ossgss..if he Nosed over at 400Knts @ 40 Degrees,or Nosed up suddenly..all is moot..

Quickly..
Member Since: July 3, 2005 Posts: 426 Comments: 128645
1154. Patrap
Updrafts and Downdrafts above Flt Level 30K can Flip the Largest Aircraft in seconds if not directed around the Updrafts and downbursts,,some that can reach vertical and horizontal speeds in excess or 150mph,over a few hundred feet across to a Mile.

If the Aircraft encountered such forces unexpectedly..nothing can prevent Catastrophe of the Airframe if the G-forces get to Gimbal Lock,,..and control is lost.

A break up occurs when the Airframe tolorences are exceeded.
Member Since: July 3, 2005 Posts: 426 Comments: 128645
1152. Ossqss
Quoting Patrap:


There is No evidence of a Terror strike on the Air France Aircraft,no one has claimed responsiblity as that is always a Drum beater.



Updrafts and Downdrafts are more Likely to Have overwhelmed the Aero Surfaces and the Flight Control systems which did fail and well,thats a Bad way to Fly.
That and the inability of the Flight Crew to have adequate time to report Verbally a problem,point to a in-flight break up.

A lot will hinge on weather they can retrieve the CVR and FDR.
Until then,..all we have are maintence records and the Digitally sent data from the Flight.


Which was more than first reported.


Could have been the technology too -- Quote from the link below. No way to overcome manually.

The new Airbus 330 was a “fly-by-wire” plane, in which signals to move the flaps are sent through electric wires to small motors in the wings rather than through cables or hydraulic tubing. Fly-by-wire systems can automatically conduct maneuvers to prevent an impending crash, but some Airbus jets will not allow a pilot to override the self-protection mechanism.

On both Qantas flights, the planes’ inertia sensors sent faulty information into the flight computers, making them take emergency measures to correct problems that did not exist, sending the planes into sudden dives.

If the inertia sensor told a computer that a plane was stalling, forcing it to drop the nose and dive to pick up airspeed, and there was simultaneously a severe downdraft in the storm turbulence, “that would be hard to recover from,” Mr. Weber said.


2 day old
Member Since: June 12, 2005 Posts: 6 Comments: 8186
1151. Levi32
Quoting MrstormX:
Someone remarked way, way earlier probably between comments 700-900 that something may go on off of the carolinas' in a day or two can we find any indication of that?


Just the low currently moving through Arkansas moving off the eastern seaboard near there. Nothing tropical.
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1150. Patrap
The next storm
As a new hurricane season begins, lessons learned can help keep us safe


Copyright 2009 Houston Chronicle
May 30, 2009, 3:29PM

With the ravages of Hurricane Ike still all too apparent along the upper Texas coast, another hurricane season is upon us. Showing nature’s disregard for the man-made meteorological calendar for a third straight year, the first tropical system of 2009 has already popped up in the Atlantic off the East Coast and then swiftly dissipated.

No two storm cycles are alike, so no one knows if the coming months will be as cruel to Southeast Texas residents as 2008, the second most destructive season on record for the U.S. with $54 billion in losses. Only 2005, the season that included Katrina’s catastrophic flooding of New Orleans and Rita’s strike on the Texas-Louisiana border, was worse, with $128 billion in damages.

In the last four years Lone Star emergency management officials have learned some valuable lessons. After the chaotic and deadly flight from Rita jammed area freeways, the carefully staged evacuations prior to Ike went smoothly, and people outside flood zones mostly heeded directives to remain in their homes.

For those away from the coast, the major hardship incurred during Ike was widespread power failures that lasted weeks in some areas. CenterPoint Energy spokesman Floyd LeBlanc calls the hurricane “a category tree storm” because most of the outages resulted from trees outside the utility right of ways falling onto power lines. Since the storm, CenterPoint has been removing trees damaged during the hurricane, as well as getting permission from home-owners to cut down trees on their property that might pose a threat.

Despite those improvements, Le-Blanc says Houstonians should keep in mind that if a major hurricane strikes, they can expect loss of power for weeks. Standard supplies to put on the shelf this season include batteries for flashlights, radios and cordless TVs, bottled water and generators. Keep in mind that generators should always be placed in well-ventilated areas outside the home to prevent accumulation of dangerous carbon monoxide fumes.

Member Since: July 3, 2005 Posts: 426 Comments: 128645
For a lay person who knows nothing about flying.....I am amazed that a state of the art airplane that was less than four years old could be destroyed in the air.......I just don't understand it :(
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1148. Patrap
UNYSIS 10-Day GFSx
Member Since: July 3, 2005 Posts: 426 Comments: 128645
Quoting MrstormX:
Someone remarked way, way earlier probably between comments 700-900 that something may go on off of the carolinas' in a day or two can we find any indication of that?


Okay post 848
Member Since: May 27, 2009 Posts: 0 Comments: 4438
1145. Levi32
Quoting jeffs713:


The GFS has an obsession with turning the normal columbian low into something tropical. Every few weeks, it spins it up and moves it north on runs about 7-10 days out. And every time, it drops it after a few runs.


That's true, but this time we have a trough split dipping into the NW Caribbean and a tropical wave moving in as well. That's a good trigger right there.
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Someone remarked way, way earlier probably between comments 700-900 that something may go on off of the carolinas' in a day or two can we find any indication of that?
Member Since: May 27, 2009 Posts: 0 Comments: 4438
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It's interesting all the comments on Hurricane Andrew. Having lived in Homestead at the time, I always thought that Andrew was a 4 but that there were so many tornados within this storm that it was easy to assume it was a cat five.

The damange was so extensive, but in certain parts of Homestead it just looked like a bomb went off.

It's funny how your mind can remember stuff so vivid after the fact. I worked at Homestead Air Force base and on late Friday afternoon I walked over to the Customs Air Branch to check on the weather. We were planning to go boating...trust me when I say NO ONE was worried about any hurricane. It was not until the next morning on Saturday that the alarm was sounded.

To this day, I don't know how thousands and thousands of people did not die in this storm.

I had thought that the equipment had broken at 180 MPH on the base? I went onto the base a couple of weeks after the storm, to "try" and salvage anything of value in our offices....( confidential papers) but I am sure most people know this was an attempt that was just not possible.

I personally will never forget the majority of my friends who had to run from room to room, as there roofs were being torn off with tiny children. I thank God I stayed with my parents in Kendall!

One block from my parents home, Wayside Baptist Church's entire side of the church was gone....a tornado. I was stunned....until I drove into Homestead days later.
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Quoting naplesdreamer28:
Early start to the season for FL?


Maybe we will have to see.
Member Since: May 27, 2009 Posts: 0 Comments: 4438
Quoting 7544:
this is getting iteresting the new run
Link


The GFS has an obsession with turning the normal columbian low into something tropical. Every few weeks, it spins it up and moves it north on runs about 7-10 days out. And every time, it drops it after a few runs.
Member Since: August 3, 2008 Posts: 16 Comments: 5885
1137. gator23
Quoting cjswilmingtoneye:

I strongly agree.


As i tell everyone, it only takes 1.
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Early start to the season for FL?
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1135. Patrap


There is No evidence of a Terror strike on the Air France Aircraft,no one has claimed responsiblity as that is always a Drum beater.



Updrafts and Downdrafts are more Likely to Have overwhelmed the Aero Surfaces and the Flight Control systems which did fail and well,thats a Bad way to Fly.
That and the inability of the Flight Crew to have adequate time to report Verbally a problem,point to a in-flight break up.

A lot will hinge on weather they can retrieve the CVR and FDR.
Until then,..all we have are maintence records and the Digitally sent data from the Flight.


Which was more than first reported.
Member Since: July 3, 2005 Posts: 426 Comments: 128645
love reading the discussions here. taking a break for the night. Have a good one everyone
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Quoting stormpetrol:


Fact IS nobody really knows, its just a scientific guess based on the same/similiar weather patterns and realistically speaking they could change on a dime.

I strongly agree. Im not saying they are wrong or right. Just sayin that they do issue numbers(noaa/cpc/hrd/nhc) just like everyone else. Except, they do it with a spin, and put a range out there. Either way the use of a number is involved. LOL
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1130. Ossqss
Quoting Levi32:


Hard to believe there could there be no lightning in that:



I don't disagree, but that is what they just presented on TWC with the main man.

If you have a start over option, use it and see for your self. I was surprised ...
Member Since: June 12, 2005 Posts: 6 Comments: 8186
1129. gator23
Quoting 7544:
this is getting iteresting the new run
Link


at 114 hours I would not put to much stock in the forcast models
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1128. Levi32
Quoting Ossqss:
It is interesting to view TWC talk, just now, of the plane crash and showed there was no lighting near the site of trouble. They say it more than likely did not happen via two services that track it. Wow.

Without lightning, the chance of it being a terror strike grow significantly. Just my take.


Hard to believe there could there be no lightning in that:

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st simon....

i find it wierd that the NWS decieded to place a track for the galvaston hurricane AFTER it already hit land (as shown on sep 9th 1900). yet that exact same track, which could have possibly saved ppls lives, is missing from the forcast on the 7th or 8th.

is it possible that the NWS put the track in AFTER THE FACT just to cover their a$$es? and from all research i have done, storm warning were not issued in galvaston until only a few hours before landfall. not a very good forecast considering a cat 4 is barreling down on them. but then again, the NWS did say strong winds POSSIBLE, thus coving their a$$es once again.
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1126. Ossqss
It is interesting to view TWC talk, just now, of the plane crash and showed there was no lighting near the site of trouble. They say it more than likely did not happen via two services that track it. Wow.

Without lightning, the chance of it being a terror strike grow significantly. Just my take.
Member Since: June 12, 2005 Posts: 6 Comments: 8186
1125. 7544
this is getting iteresting the new run
Link
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Quoting cjswilmingtoneye:
I'm a little confused about something:
(the following is from the NHC's may 2009 outlook for this hurricane season)
"we estimate a 70% probability for each of the following seasonal ranges:

9-14 Named Storms,
4-7 Hurricanes
1-3 Major Hurricanes,
An ACE range of 65%-130% of the median ."
So if they dont issue a numerical "scientific best guess", what would this be considered? Just a little confused.


Fact IS nobody really knows, its just a scientific guess based on the same/similiar weather patterns and realistically speaking they could change on a dime.
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Quoting clwstmchasr:
What an exciting night. Just watched with my kids a combination of the Rays and Jeff Niemann blow out the Royals and Home Alone 2 for the 43rd time.

Looks like a couple of wet days here on the west coast of FL.


Lets hope that Caribbean storm doesn't dump to much on you guys.
Member Since: May 27, 2009 Posts: 0 Comments: 4438
Quoting Patrap:


NOAA issues that,not the NHC



NOAA: 2009 Atlantic Hurricane Season Outlook

Issued: 21 May 2009

Right. But NHC does contribute to it, along with the HRD.
"The 2009 Atlantic hurricane season outlook is an official product of the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (CPC), and is produced in collaboration with scientists from the National Hurricane Center (NHC) and Hurricane Research Division (HRD)."
Just saying that the idea that at some point their could be political actions at play there(NHC) aren't so far fetched. I believe they do the best job they can do, and am very thankful for the watches/warnings. Especially, having been a victim of the floods of Hurricane Floyd(1999), and the destructive winds of Hurricane Fran(1996). But, by no means are they perfect. Especially when you consider the fact that 90 L was definatley a Tropical Storm at landfall. It just was, all evidence supports this conclusion. The unnamed storm that passed over the Albemarle and Pamlico sounds in North Carolin in 2006 is another perfect example. These were probably not politcally motivated moves, but the NHC can and probably will make more mistakes they aren't perfect.
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1119. Patrap
A lil more in-depth on the Subject matter sports fans.


NASA Finds Intense Lightning Activity Around a Hurricane's Eye

June 23, 2006



When you think of lightning, you think of a thunderstorm. Many people also assume that hurricanes have a lot of lightning because they are made up of hundreds of thunderstorms.

However, according to Dr. Richard Blakeslee of the NASA Marshall Space Flight Center (MSFC) in Huntsville, Ala., "Generally there's not a lot of lightning in the hurricane eye-wall region. So when people detect a lot of lightning in a hurricane, they perk up -- they say, okay, something's happening."

In 2005, scientists did perk up, because a very strong Hurricane Emily had some of the most lightning activity ever seen in a hurricane. Scientists are now trying to determine if the frequency of lightning is connected to the hurricane's strength.

In July of that year, NASA lightning researchers joined hurricane specialists from the National Oceanic and Atmospheric Administration (NOAA) and 10 universities for a month-long Tropical Cloud Systems and Processes (TCSP) field experiment in Costa Rica. The purpose of the mission was to determine what weather, climate and other factors that helped create tropical storms and hurricanes. They also wanted to learn about what makes these storms strengthen. All of these organizations study lightning in hurricanes to get a better understanding of the strengthening or weakening (intensification) of the storms.
Member Since: July 3, 2005 Posts: 426 Comments: 128645
1118. Patrap
Only the Narrow minded belays the word..LOL
Member Since: July 3, 2005 Posts: 426 Comments: 128645
1117. Patrap
Quoting cjswilmingtoneye:
I'm a little confused about something:
(the following is from the NHC's may 2009 outlook for this hurricane season)
"we estimate a 70% probability for each of the following seasonal ranges:

9-14 Named Storms,
4-7 Hurricanes
1-3 Major Hurricanes,
An ACE range of 65%-130% of the median ."
So if they dont issue a numerical "scientific best guess", what would this be considered? Just a little confused.


NOAA issues that,not the NHC



NOAA: 2009 Atlantic Hurricane Season Outlook

Issued: 21 May 2009


Interpretation of NOAA's Atlantic seasonal hurricane outlook
This outlook provides a general guide to the expected overall nature of the upcoming hurricane season. This outlook is not a seasonal hurricane landfall forecast, and it does not imply levels of activity for any particular region.
Member Since: July 3, 2005 Posts: 426 Comments: 128645
1116. Levi32
Quoting cjswilmingtoneye:
I'm a little confused about something:
(the following is from the NHC's may 2009 outlook for this hurricane season)
"we estimate a 70% probability for each of the following seasonal ranges:

9-14 Named Storms,
4-7 Hurricanes
1-3 Major Hurricanes,
An ACE range of 65%-130% of the median ."
So if they dont issue a numerical "scientific best guess", what would this be considered? Just a little confused.


It's the same thing as the official forecast issued by NOAA. I just dislike the broad probabilities and number ranges.
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Quoting StSimonsIslandGAGuy:
Canewarning where were you in that image in comment 1087?


Just west of the "S" in U.S. 1 north of HAFB.
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Quoting weatherblog:
I think we should already have been to Claudette.

90L should have been Ana, TD 1 should have been Bill, and 92L should have been Claudette.

While it's just my opinion, they all at one point were a TS.


90L should have been Ana
Member Since: May 27, 2009 Posts: 0 Comments: 4438
1113. gator23
Quoting TampaFLUSA:

What 9 ppl (?) died in Florida bc they thought Katrina was just a Cat 1 and blew it off...people don't realize all it takes is that falling tree....
Quoting TampaFLUSA:

What 9 ppl (?) died in Florida bc they thought Katrina was just a Cat 1 and blew it off...people don't realize all it takes is that falling tree....


yep, it was 14 deaths
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1112. Levi32
"Somehow the convection of these thunderstorms within the hurricane seems to organize the hurricane better and improve its rotation," Price said.

Not sure why he said it as if we don't already know why that happens.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.