Tropical Storm Danny likely to be named today

By: Dr. Jeff Masters , 1:25 PM GMT on August 26, 2009

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First-light satellite images of the tropical wave (92L) a few hundred miles northeast of the Bahama Islands show that the system has developed an organized surface circulation, and 92L will likely be named Tropical Storm Danny later today. This morning's QuikSCAT pass confirms the presence of a surface circulation, and the satellite saw top winds of 50 mph in a cluster of thunderstorms well east of the center. Wind shear has dropped to the moderate range, 10 - 15 knots. The upper-level low 92L is moving underneath has plenty of dry air in it, and the upper low is injecting this dry air into 92L's west side, keeping and heavy thunderstorm activity from developing on that side. The Hurricane Hunters are in 92L, and have found surface winds up to 57 mph so far this morning. NHC continues to give 92L a high (greater than 50% chance) of developing into a tropical depression by Thursday afternoon.


Figure 1. Water vapor satellite image from 8:15 am EDT 8/26/09 showing dry air associated with an upper-level low pressure system to the west of 92L's center of circulation. Image credit: NOAA/SSD.

The forecast for 92L
As 92L continues to plow through the upper low, the low will weaken, and wind shear is expected to decline to the low range, 5 - 10 knots, by tonight. However, the upper-level low will continue to dump dry, cold air into 92L through Thursday afternoon, slowing down development. By Thursday night, when 92L should be several hundred miles off the coast of northern Florida, the upper-level low may be weak enough and far enough away that 92L will find itself in a region with light upper level anticyclonic winds, which would favor more rapid development. Most of the intensity models, including the GFDL, HWRF, and SHIPS model, forecast that 92L 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 92L to the north. The models have come into better agreement keeping 92L offshore as it passes North Carolina, though the storm is certainly capable of giving the Outer Banks a direct hit. As 92L passes North Carolina, it should start heading north-northeast, with a second landfall likely Saturday night or Sunday morning somewhere between Massachusetts and Nova Scotia. At that time, 92L is likely to be a strong tropical storm or weak Category 1 hurricane, with winds in the 55 - 80 mph range. It currently appears that 92L will not bring tropical storm-force winds to the Bahamas or to Florida.

Elsewhere in the Atlantic
The models have been inconsistently predicting formation of several tropical waves coming off the coast of Africa over the next week, and I am going to stop mentioning these forecasts until we get two models predicting the same thing, several model runs in a row.

I'll have an update later today.

Jeff Masters

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With all of the troughs digging down, it looks more like October.
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Quoting OSUWXGUY:
Alright...this is the last NAM image I'll post...

Simulated reflectivity showing a broad eye-like feature just SSE of New York City.

At this time, the upper level 200/300mb pattern is massively divergent over the storm. The storm finds itself in the right rear quadrant of the northern jet, with a pattern very similar to the setup for a blizzard that is bombing out off the coast of the Northeast!



Yikes! Cat 3 or 4? Looks like the wishcasters (cough Bastardi cough) might actually get their major hurricane hitting NY.
Member Since: August 14, 2008 Posts: 0 Comments: 137
Quoting surfmom:
caicos/post 194 - timing is everything - Virgina Beach Surfing Contest.... could be EPIC


bring it on surfmom!!
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LOL surfmom forgot thats comming up LOL EPIC Right Coast surfing contest. Either way they wont be worring about flat conditions
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Danny is born...New York is in the cone....yikes...bastardi might finally get one right.....
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caicos/post 194 - timing is everything - Virgina Beach Surfing Contest.... could be EPIC
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biggest threat to NJ currently will be the torrential rains which will lead to flooding of small streams and urban areas. some main stem rivers might be affected as well.

through in a little wind and trees can start coming down so power outages are a factor to consider as well.

I will be getting 20 more gallons for the genny before the panic hits. No news services have said the H word up here yet
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At this point, if Danny doesn't develop a western side, you could see a landfalling tropical storm with sunshine :)
Member Since: August 14, 2008 Posts: 0 Comments: 137
259. 7544
Quoting SeniorPoppy:


I thought they were being more cautious about naming storms this year.


looks like they had no choice if this was further out in the cen atl it would have not been name today but its so close to the bammas and if it did decide to go further west which it still might they had to make the call for a ts
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wow, they named that??
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Alright...this is the last NAM image I'll post...

Simulated reflectivity showing a broad eye-like feature just SSE of New York City.

At this time, the upper level 200/300mb pattern is massively divergent over the storm. The storm finds itself in the right rear quadrant of the northern jet, with a pattern very similar to the setup for a blizzard that is bombing out off the coast of the Northeast!

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Quoting violetprofusion:


I live to the southwest of Newark, should I start building a hurricane preparedness kit now? Hahaha, probably not, but I'm a wimp about these things. I am so, so wimpy about being anywhere near a forecast cone.


At least we don't have to worry about any storm surge if a big system were to be knocking on our doorstep...we're more than 30 miles inland. However my area is prone to flood waters from the Passaic River.
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IKE-

They named it because it's 48-60 hours from landfall, perhaps 72-84 from landfall in major cities across New England. Naming it gets the word out for preparations to begin.
Member Since: August 22, 2006 Posts: 0 Comments: 1451
253. IKE
Quoting Patrap:


Proximity to JFV's House was the determining factor I bet IKE.


Must be. It looks terrible.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting Patrap:


Proximity to JFV's House was the determining factor I bet IKE.


Lmao
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Quoting IKE:
EXPOSED! I'm shocked they named this. Completely exposed.



I thought they were being more cautious about naming storms this year.
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249. MahFL
Holy poop Danny !!
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Quoting IKE:
EXPOSED! I'm shocked they named this. Completely exposed.



Proximity to JFV's House was the determining factor I bet IKE.
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Quoting StormW:


Tomorrow.

Thanks BTW!


happy birthday storm..btw can you make a wish for me..keep hurricanes of the coast for the remainder of the season..pleeeeeease..blow your candles tomorrow and wish for the fishes.
Member Since: August 18, 2009 Posts: 0 Comments: 157
Hurricane Preparation Entry
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I dont think the models are done shifting WEst just yet...
243. IKE
EXPOSED! I'm shocked they named this. Completely exposed.

Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting Bonedog:
dont like the 12Z ECMWF



Uhh...me neither. CMC and NAM now both on same track?
Member Since: September 12, 2007 Posts: 0 Comments: 725
Quoting TerraNova:


I'm on it (Newark, NJ is just east of me), I have a 13% chance of TS winds Sat/Sun.


I live to the southwest of Newark, should I start building a hurricane preparedness kit now? Hahaha, probably not, but I'm a wimp about these things. I am so, so wimpy about being anywhere near a forecast cone.

(I'm mostly joking here, but I'm originally from the Midwest--I've never lived so near a coast before and I'm extremely silly about these things.)
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Quoting Bonedog:
dont like the 12Z ECMWF



LOL. That's the ECMWF from two days ago since that model's data is delayed by two days on that site (kinda stupid, I know), for the most recent ECMWF run go here.
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Quoting Bonedog:
dont like the 12Z ECMWF



Ok now thats 3 models, CMC, NAM, and ECMWF that hit me..................... seriously going out for supplies later today. sigh...
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IKE just noticed that LOL I posted the wrong one. Im getting things together. LOL thanks for the spot
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Hello Danny
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234. IKE
Quoting Bonedog:
dont like the 12Z ECMWF



That's from 2 days ago.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
i find it intresting that a shallow system can be steered by a trof i thought only strong systems feel the effects of trofs
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12Z models are gonna be interesting. When do the first ones finish?
Member Since: August 22, 2006 Posts: 0 Comments: 1451
for VA, and NC residents.
- - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - -

FROM FROM FROM FROM FROM FROM FROM
TIME 12Z WED 00Z THU 12Z THU 00Z FRI 12Z FRI 12Z SAT 12Z SUN
PERIODS TO TO TO TO TO TO TO
00Z THU 12Z THU 00Z FRI 12Z FRI 12Z SAT 12Z SUN 12Z MON

FORECAST HOUR (12) (24) (36) (48) (72) (96) (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
LOCATION KT



NORFOLK VA 34 X X( X) X( X) 1( 1) 19(20) 5(25) X(25)
NORFOLK VA 50 X X( X) X( X) X( X) 4( 4) 3( 7) X( 7)
NORFOLK VA 64 X X( X) X( X) X( X) 1( 1) 1( 2) X( 2)

GREENSBORO NC 34 X X( X) X( X) X( X) 4( 4) X( 4) X( 4)

RALEIGH NC 34 X X( X) X( X) X( X) 7( 7) 1( 8) X( 8)

CAPE HATTERAS 34 X X( X) X( X) 4( 4) 33(37) 5(42) X(42)
CAPE HATTERAS 50 X X( X) X( X) X( X) 13(13) 3(16) X(16)
CAPE HATTERAS 64 X X( X) X( X) X( X) 5( 5) 1( 6) X( 6)

MOREHEAD CITY 34 X X( X) X( X) 5( 5) 26(31) 2(33) X(33)
MOREHEAD CITY 50 X X( X) X( X) 1( 1) 8( 9) 1(10) X(10)
MOREHEAD CITY 64 X X( X) X( X) X( X) 2( 2) 1( 3) X( 3)

WILMINGTON NC 34 X X( X) X( X) 4( 4) 16(20) 1(21) X(21)
WILMINGTON NC 50 X X( X) X( X) X( X) 4( 4) X( 4) X( 4)
WILMINGTON NC 64 X X( X) X( X) X( X) 2( 2) X( 2) X( 2)

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removed by poster. wrong date
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Official TS Danny has formed. Question did WU make a mistake or is there another systme right next to Danny called 92?
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Apparently the NAM has started smoking the same stuff as the CMC. They're starting to look more and more alike.

Now I will be impressed if they're actually right...

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Accuweather Track with US landfall.

Member Since: August 14, 2008 Posts: 0 Comments: 137
Quoting nrtiwlnvragn:
Wind Speed Probabilities

Check if your location is on the list.


I'm on it (Newark, NJ is just east of me), I have a 13% chance of TS winds Sat/Sun.
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Looks like this could be the year for NE hits...
Member Since: October 18, 2005 Posts: 4 Comments: 3052
The disturbance in the SW Carribean might be one to watch also.
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Quoting SeniorPoppy:
Florida still has the force field up. The troughs keep on comming down. It is amazing that this is happening in August. I hope the east coast is spared with Danny boy.


lets hope it stays this way..hurricanes are not welcome..no vacancy
Member Since: August 18, 2009 Posts: 0 Comments: 157
Well, drat, I'm in the cone. But hopefully by the time it gets up here it'll just be blustery rain and rough tide.
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Quoting Gumbogator:
Danny Boy, Da pipes Da pipes


If anyone posts a Youtube song of Danny boy, I am out of here, Like the one from the 60's "Don't mess with Bill" It was funny though!
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Florida still has the force field up. The troughs keep on comming down. It is amazing that this is happening in August. I hope the east coast is spared with Danny boy.
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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.