Tropical Storm Danny not impressive yet

By: Dr. Jeff Masters , 7:19 PM GMT on August 26, 2009

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Tropical Storm Danny is here, born from an African tropical wave that developed a closed circulation and some respectable heavy thunderstorm activity this morning. Data between 2 - 3 pm EDT from the Hurricane Hunters indicates the Danny has a central pressure of 1009 mb, and top surface winds of about 45 mph. Satellite imagery shows that Danny's circulation has gotten stretched and pulled away from the heaviest thunderstorm activity on the storm's east side. It is possible that Danny's center will reform at a different location, closer to the heaviest thunderstorms, so the model forecasts probably have a higher degree of uncertainty than usual at present. Wind shear has dropped to the low range, 5 - 10 knots. The upper-level low Danny is moving underneath has plenty of dry air in it, and this dry air is intruding into Danny's west side, keeping and heavy thunderstorm activity from developing on that side.


Figure 1. Oceanic heat content for August 25, 2009. Regions where the Sea Surface Temperature is below 80°F, or where the shallow waters of the Continental Shelf lie, do not have enough heat content to be plotted, and are shown in white colors. The oceanic heat content along the track of Tropical Storm Danny is below the threshold of 90 kJ/cm^2 typically seen with cases of rapid intensification. The storm position at 8am EDT today is given by the hurricane symbol with the "0" inside it. Subsequent hurricane symbols show the official NHC forecast points from the 11 am EDT forecast today, for 8am Thursday (24 hours), 8am Friday (48 hours), 8am Saturday (72 hours), and 8am Sunday (72 hours). The cold waters stirred up by Hurricane Bill last week will not impact Tropical Storm Danny. Image credit: RSMAS, University of Miami.

The forecast for Danny
As Danny continues to plow through the upper low, the low will weaken, but will dump dry air into the storm through Thursday afternoon, slowing down development. By Thursday night, when Danny should be several hundred miles off the coast of northern Florida, the upper-level low may be weak enough and far enough away that Danny will find itself in a region with light upper level anticyclonic winds, which would favor more rapid development. Ocean heat content (Figure 1) is high enough to support a hurricane, until Danny gets to about New Jersey's latitude. Most of the intensity models, including the GFDL, HWRF, and SHIPS model, forecast that Danny will become a hurricane by Friday. However, this favorable environment will not last long, since a strong trough of low pressure will be approaching the U.S. East Coast on Friday. This trough will bring high wind shear of 20 - 30 knots by Friday night. This trough should be strong enough to turn Danny to the north, then northeast on Saturday. The models have come into better agreement keeping Danny offshore as it passes North Carolina, though the storm is certainly capable of giving the Outer Banks a direct hit. As Danny passes North Carolina, it should start heading north-northeast, with a landfall likely Saturday afternoon or evening somewhere between Massachusetts and Nova Scotia. At that time, Danny is likely to be a strong tropical storm or weak Category 1 hurricane, with winds in the 55 - 80 mph range. The latest runs of the GFDL and GFS model have Danny tracking directly over Martha's Vineyard, where President Obama is on vacation. It will be interesting to see if the president stays on the island for Danny.

For those of you wondering about specific probabilities of getting tropical storm force or hurricane force winds, consult the NHC Wind Probability Product.


Figure 2. Tropical wave newly emerged from the coast of Africa, with some potential for development.

Elsewhere in the Atlantic
A well-organized tropical wave has exited the coast of Africa, and lies a few hundred miles southeast of the Cape Verdes Islands. None of the models are gung-ho about developing this wave, but shear is low, 10 knots, and waters are warm enough to support development. The dry Saharan Air Layer is relatively limited in extent and intensity, so dry air may have only a small inhibiting effect on the wave. Expect some slow development of this wave as it moves westward over the next few days. NHC is giving this system a low (less than 30% chance) of developing into a tropical depression by Friday afternoon.

I'll have an update Thursday.

Jeff Masters

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LOL! The blob on the bottom right corner of the screen has a higher chance (med. 30-50%) of developing in the next 48 hrs. than our African wave, which has a low chance to develop in the next 48 hrs. Not so sure about that.
Member Since: June 29, 2009 Posts: 13 Comments: 5300
People say that steering patterns change all the time, but doesn't it seem like each year brings a different trend. For example, 2004 it seemed like everything hit Florida (in fact Jeanne and Francis both made landfall in the same place). Last year was the year for Texas storms. Looks like this year is the year for either fish storms or New England storms. Here's betting the wave off Africa ends up at one of those two places.
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Quoting aquak9:
Well...if anyone is that curious, here's the REAL Phil Ferro's email address:

PFerro@wsvn.com

Tell'm his "friend" at the Taco Bell drive-thru said hi.
lol, i know phil very well, and that is not him for sure.
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A)
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Still yellow:


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Well...if anyone is that curious, here's the REAL Phil Ferro's email address:

PFerro@wsvn.com

Tell'm his "friend" at the Taco Bell drive-thru said hi.
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Quoting btwntx08:
quick cv wave will be what color at 8 pm
A.yellow
b.orange
c..red
d.circle gone
b or c
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8PM is out its still yellow
Member Since: September 6, 2007 Posts: 0 Comments: 6141
Quoting klaatuborada:


It's a Tropical Wave, it's a Tropical Storm, it's a Hurricane
It's going West, it's going East
It's Phil Ferro, it's not Phil Ferro
He can spell, he can't spell
It's a run on sentence, it's not a run on sentence
I am a hairclub member, I am also it's president

Now, back to the weather...


AMEN!!!! LOL
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LOL @ 480!
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He better start turning right! I could hit the COC from Miami beach with my Penn 1.
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Quoting RyanFSU:
HWRF 18Z still east of MASS.
GFDL 18Z has moved eastward as well...just misses MASS.





The Cape is still getting hit in that. We're the part sticking out like a sore arm.
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Quoting JupiterFL:


Why did you email me yesterday and tell me you were the "real" Phil Ferro. By the way, do you know what a run on sentence is?


sniff sniff... smell that? smells like a defamation lawsuit!!
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That front currently shown on reedzone's map is suppose to move as far south as the Ohio River Valley region, stall out, and then move north as a warm front on Friday. The cold front further north in Canada is the strong one coming through on Saturday, which will push the weak one along. At least that is the current forecast from the NOAA says for my area.
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TD 1, 98L, Bill and Danny all curved up the East Coast under persistent troughing, three of those could potentially impact New England, this year is a New Engaland Season.

98L brough TS conditions to New England late July

Bill brought high surf and gusty winds

Danny could potentially bring a combination of both.
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HWRF 18Z still east of MASS.
GFDL 18Z has moved eastward as well...just misses MASS.



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Quoting NRAamy:
oh, so it's ok for everyone else to rag on JFV, but if I do it, I get banned....now I understand the rules....


If you want to get banned, simply state something a little right of center.

ie.. Global Warming is not man made.

(Disclaimer: This is only an example, and may or may not reflect the views of the this moronic poster)
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Guess what. I am taking a break. When I start correcting other people's grammar corrections of other people, it is time to do something else for a while.

After all, it IS a weather blog, not a grammar blog.
Member Since: October 25, 2005 Posts: 19 Comments: 21537
U know what is funny. I am a friend of his on facebook and he told me that he has never visited this site, sooooooooo, of course "PhilFerro" is fake.
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Quoting extreme236:
Center will probably reform again closer to the convection...was never really a vigorous one anyway.


idk 236 i think this blow up of cnvection is building toward the current coc, i think you can see it the semi-circle is that it?near 25.5N 72W?
Member Since: September 6, 2007 Posts: 0 Comments: 6141
Quoting JupiterFL:


Why did you email me yesterday and tell me you were the "real" Phil Ferro. By the way, do you know what a run on sentence is?
This is technically not a run on sentence.
Member Since: October 25, 2005 Posts: 19 Comments: 21537
Quoting JupiterFL:


Why did you email me yesterday and tell me you were the "real" Phil Ferro. By the way, do you know what a run on sentence is?
leave him, obviously s fake.
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Quoting JupiterFL:


Why did you email me yesterday and tell me you were the "real" Phil Ferro. By the way, do you know what a run on sentence is?


He just doesn't know how to use the semi-colon.
Member Since: October 28, 2006 Posts: 57 Comments: 29919
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Quoting PhilFerro:
I am not Phil Ferro, I am a friend of his, and yes I do know him.


Why did you email me yesterday and tell me you were the "real" Phil Ferro. By the way, do you know what a run on sentence is?
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Center will probably reform again closer to the convection...was never really a vigorous one anyway.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
Quoting reedzone:
Here's my first track for Danny. As the upper level low that's pushing Danny on a west-northwestward course at this time moves away, the next upper level low should begin pulling Danny north, but as you can see, it's not following most of the models which have it going NW by now. This should shift models a bit more westward, then Danny should be able to pull northward, possible scraping the Carolinas before heading near Cape Cod, MA. Hopefully it will be Extratropical when it reaches to that point, but can't be sure for certain just yet. The kicker for Danny will be a developing trough of Low Pressure that is currently forming in Tornado Alley. For now, the ridge of High Pressure that continues to build to Dannys north will continue steering the storm close to the CONUS. A "Hurricane Bob" like track is definitely not out of the question. Though this has a good chance at not effecting anybody at all :)

Forecast Path For Tropical Storm Danny
Photobucket


And I posted that track on previous Blog! Here it is, so alike it's scary. My comment was that Bob and Danny were cousins.



I'll take one of the "not effecting anybody at all" please
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Quoting 954FtLCane:

he's going trof a faze

philferro = jfv, aka weatherstudent, aka fish shower curtain .....
lol
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Quoting stormsurge39:
Whats up weth the spel polece in here? LOL

I gotta run. I'm deputizing you!
Member Since: September 3, 2007 Posts: 3 Comments: 1519
AHA!

Just as I thought.

"Nonetheless, oceanic convection exhibits a systematic diurnal fluctuation with maximum intensity in the early morning. "
-The Diurnal Cycle of Tropical Convection Abstract

"The Diurnal Cycle of Tropical Convection",
Harry H. Hendon, Center for Atmospheric Theory and Analysis, University of Colorado, Boulder and Karen Woodberry, Center for Atmospheric Theory and Analysis, University of Colorado, Boulder


D-max is in the EARLY MORNING, folks, not the early EVENING / late afternoon as I have seen some people post here. This has so been messing with my head of late....
Member Since: October 25, 2005 Posts: 19 Comments: 21537
Member Since: October 28, 2006 Posts: 57 Comments: 29919
465. 7544

the front over fla died out and the uul is moving due west pulling danny along at this hour any recon reports
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Quoting aquak9:
blogger philferro is simply re-gurgitating from the REAL Phil Ferro's blog, that's all.

Happened last year, too, with the CrownWeather site, someone impersonating him.

seems to happen every year...
Phil ferro will quickly die out as soon as we find out, seems dead already. And if you notice what is on his blog, is what he wrote in his real phil factor blog on wsvn 7 site.
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oh, so it's ok for everyone else to rag on JFV, but if I do it, I get banned....now I understand the rules....
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Quoting stormsurge39:
Whats up weth the spel polece in here? LOL


i mean if you cant even get 50% of the letters right... hahahaha
Member Since: September 6, 2007 Posts: 0 Comments: 6141
NEW ENTRY POSTED:
South Florida StormWatch
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Quoting CatastrophicDL:

I think Phil would know how to spell :o)

he's going trof a faze

philferro = jfv, aka weatherstudent, aka fish shower curtain .....
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Flood, sorry if I seemed rude and lacking a timely response earlier...had some intermittent power issues here in the OKC
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Whats up weth the spel polece in here? LOL
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Here's my first track for Danny. As the upper level low that's pushing Danny on a west-northwestward course at this time moves away, the next upper level low should begin pulling Danny north, but as you can see, it's not following most of the models which have it going NW by now. This should shift models a bit more westward, then Danny should be able to pull northward, possible scraping the Carolinas before heading near Cape Cod, MA. Hopefully it will be Extratropical when it reaches to that point, but can't be sure for certain just yet. The kicker for Danny will be a developing trough of Low Pressure that is currently forming in Tornado Alley. For now, the ridge of High Pressure that continues to build to Dannys north will continue steering the storm close to the CONUS. A "Hurricane Bob" like track is definitely not out of the question. Though this has a good chance at not effecting anybody at all :)

Forecast Path For Tropical Storm Danny
Photobucket
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Quoting weathercrazy40:
ok whats the thinking here for southeastern mass


On my Centerville weather forecast, WU now says, Saturday, 60% chance of Rain, Hurricane Danny.

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Quoting UWalkTheMall:
It is Phil Ferro. It isn't Phil Ferro. Will the real Phil Ferro please shout out. lol!

I think Phil would know how to spell :o)
Member Since: September 3, 2007 Posts: 3 Comments: 1519
Quoting Weathermandan:
Okay question (again lol) what is the "corrected model consensus" exactly? The NHC quoted it in their 5 PM discussion as the reason for shifting the forecast track to the EAST while all the models I'm looking at and that are quoted in their discussion have shifted westward (on average, GFS moved west, NAM moved east, closer together but on average further west).

And this flare-up of convection, perhaps the center will re-develop near or under these thunderstorms and because of much lower shear Danny may organize a little more overnight? Or am I jumping the gun, I feel like I am but it looks slightly better than before.


actually the thunderstorms are blowing up near and building toward current COC.
Member Since: September 6, 2007 Posts: 0 Comments: 6141
blogger philferro is simply re-gurgitating from the REAL Phil Ferro's blog, that's all.

Happened last year, too, with the CrownWeather site, someone impersonating him.

seems to happen every year...
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ok whats the thinking here for southeastern mass
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lets forget about phil ferro
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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.

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