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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re:104

thats highly probable with Danny. Might be more east or west of that but its a possiblity. dont think the intensity will be that strong but who knows with a hot gulf stream
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Quoting mikatnight:


You sure? They're not normally scheduled until 2pm, right?


They can start advisories at 2 AM/PM, 5 AM/PM, 8 AM/PM, and 11 AM/PM. 2 and 8 o'clock are usually special/intermediate advisories while 11 and 5 are normally complete advisories. They usually issue first advisories at 11 or 5.
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Link I have my new blog up on dannys tracks and intensity.
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Just don't see this getting too strong,not a lot of time to acquire a lot of strength,although when it gets to the GS,it will get a quick burst.
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Danny

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storms trying to wrap around the north side of the circulation
Member Since: September 6, 2007 Posts: 0 Comments: 6485
Quoting ncstorm:


Thanks..so why is the blog saying the storm will pass east of NC if we dont have the correct data yet?


Hehe... is because of the models... since that's the only way for now to get a handle on this system.
Member Since: August 14, 2008 Posts: 4 Comments: 4972
All the Convection with 92L is shunted east of the CoC.



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Scheduled at 2, they'll break into regularly scheduled programming if a TC has formed.
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Morning Storm!

Keeping an eye on this one LOL

Some models showing a hit up here. First one in a long time.
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Quoting TerraNova:


If Danny has really arrived we'll see advisories by 11 o'clock.


You sure? They're not normally scheduled until 2pm, right?
Member Since: October 18, 2005 Posts: 4 Comments: 3052

Morro Castle Storm in 1934
seemed like a worst case scenario for this storm
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NHC won't update until they get the pretty maps together.
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Quoting willdunc79:
Does it say Danny on the NHC site yet? When it says it there then I'll pay the man behind the counter.

Nothing yet. Not named on the Navy site either
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Quoting 7544:
could get close to the northern bahaamas if it keeps drifting west looks like its also slowing down


Looks almost stationary or committing NW.
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according to what i see the Navy site hasnt named it yet
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Quoting willdunc79:
Does it say Danny on the NHC site yet? When it says it there then I'll pay the man behind the counter.


If Danny has really arrived we'll see advisories by 11 o'clock.
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"Oh Danny boy, the pipes, the pipes are calling..."
Member Since: October 18, 2005 Posts: 4 Comments: 3052
Does it say Danny on the NHC site yet? When it says it there then I'll pay the man behind the counter.
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I can't wait for the new location to compare to the 8am model runs....
Member Since: September 6, 2007 Posts: 0 Comments: 6485
Quoting Alockwr21:
Seems like this system has already changed a lot.

If I remember, almost all of the models were not predicting a hurricane out of this. Now, almost all models are..


It's starting to get it's groove on!!
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Seems like this system has already changed a lot.

If I remember, almost all of the models were not predicting a hurricane out of this. Now, almost all models are..
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90. 7544
could get close to the northern bahaamas if it keeps drifting west looks like its also slowing down
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Quoting GeoffreyWPB:
2009 Storms
All Active Year


Atlantic
05L.DANNY


AL052009.DANNY
40 MPH
1009MB
Member Since: September 6, 2007 Posts: 0 Comments: 6485
Quoting nrtiwlnvragn:
BEGIN
NHC_ATCF
invest_al052009.invest
FSTDA
R
U
40
10
0
200908261405
NONE
NOTIFY=ATRP
END
DANNY AL L 05 2009


nrtiwlnvragn - you make this blog enjoyable. Thanks for posting this stuff.
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Quoting Alockwr21:
Do we have Danny??


Sure looks like it to my novice eye??
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looking at the apparent swirl of clouds when Danny gets his act together he will be a rather large system
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2009 Storms
All Active Year


Atlantic
05L.DANNY
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Quoting hurricanehanna:
Does 92L have an LLC yet? It looks exposed to my eyes.


According to Dr. M, yes:

"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..."
Member Since: October 18, 2005 Posts: 4 Comments: 3052
Do we have Danny??
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Quoting VAbeachhurricanes:


We have danny! or td 5


Yeah looks like it; I was just about to post that. 12Z update on the FTP site has "Danny" at 1009mb with 40 knot winds and a COC located at 24.6N, 70.0W. Although recon hasn't issued a vortex message yet I guess NHC has seen enough that they're ready to classify this.
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Member Since: September 6, 2007 Posts: 0 Comments: 6485
ECU -

Well, my friends on Facebook know ;) I warned 'em. Now to borrow buddy's longboard and try the waves this weekend.
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Quoting OSUWXGUY:
Plenty of Oceanic Heat Content along the Gulf Stream if this thing hugs the coast south of North Carolina!

Just for reference, anything ~90 or above is supportive of rapid intensification. Fortunately, the upper air conditions don't appear like they'll be favorable enough for 92L to undergo RI.


Definitely lots of jet fuel waiting in the Gulf Stream.

Also, you can actually see Bill's general track between CONUS and Bermuda.
Member Since: August 3, 2008 Posts: 16 Comments: 5881
Models now in agreement that we will have a hurricane within 72 hours.
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BEGIN
NHC_ATCF
invest_al052009.invest
FSTDA
R
U
40
10
0
200908261405
NONE
NOTIFY=ATRP
END
DANNY AL L 05 2009
Member Since: September 23, 2005 Posts: 14 Comments: 11157
Quoting 7544:
could 92l at a 280 heading at this hour hmmm


Yes, I agree! If you put the lat. and lon. lines over the satellite it does appear that the COC is moving almost due west
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Quoting nrtiwlnvragn:
08/26/2009 02:04PM 2,113 invest_RENUMBER_al922009_al052009.ren


We have danny! or td 5
Member Since: September 6, 2007 Posts: 0 Comments: 6485
Does 92L have an LLC yet? It looks exposed to my eyes.
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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC
930 AM EDT WED AUG 26 2009

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER THE REGION THROUGH THURSDAY. AN AREA OF
DISTURBED WEATHER NORTH OF PUERTO RICO TONIGHT WILL TRACK NORTHWEST
TOWARD THE UNITED STATES COAST THROUGH THE END OF THE WEEK. THIS
WEATHER SYSTEM MAY BRING UNSETTLED WEATHER CONDITIONS BEGINNING
FRIDAY AND CONTINUING THROUGH SATURDAY. A COLD FRONT WILL MOVE SLOWLY
THROUGH THE AREA EARLY NEXT WEEK.
.LONG TERM /FRIDAY THROUGH TUESDAY/...
ALL INTERESTS ARE URGED TO MONITOR THE LATEST FORECASTS AS THE
CHANCES FOR ADVERSE WEATHER CONDITIONS WILL BE INCREASING EARLY
THIS FCST PERIOD AS TROPICAL LOW PRESSURE LIKELY APPROACHES THE
SE COAST. TOO EARLY TO GET INTO MUCH FORECAST DETAIL GIVEN THE
INEVITABLE ERRORS IN TRACK AND INTENSITY BUT THERE MAY BE A THREAT
FOR HEAVY RAIN AND GUSTY WINDS FRIDAY THRU SATURDAY. MODEL
CONSENSUS SUGGESTS THE LOW WILL BE MOVING QUICKLY TO THE NE SAT
NIGHT INTO SUNDAY SO MUCH IMPROVED CONDITIONS EXPECTED FOR THE
LATE WEEKEND INTO EARLY NEXT WEEK...ALTHO A SLOW MOVING FRONTAL
BNDRY MAY CONTINUE TO PROVIDE A FOCUS FOR ISOLATED TO SCATTERED
CONVECTION THRU THE REMAINING LONG TERM FCST PERIOD.

THERE IS LOW CONFIDENCE IN THE LATER PART OF THE WEEK AS THE MODEL
UNCERTAINTY IN THE DEVELOPMENT AND TRACK OF AN AREA OF DISTURBED
WX NEARING THE BAHAMAS COULD RESULT IN VERY DIFFERENT MARINE OUTCOMES
FOR THE NC COASTAL WATERS. THE SWELL FROM THIS SYSTEM IS
ANTICIPATED TO MOVE INTO THE AREA ON THU...GRADUALLY PUSHING SEAS
BACK UP TO NEAR SCA. THE SWELL WILL KEEP SEAS UP INTO THU NT...WITH
WINDS UNDER 15KT. USING HPC FRONT/PRESSURE PATTERN AS A GUIDE SHOW
A WEAK LOW MOVING OUT OF THE S AND PASSING THROUGH THE PAM SOUND
BY SAT. HAVE BUMPED UP THE WINDS MARGINALLY TO 15 TO 20 KT FRI
NT/SAT GIVEN UNCERTAINTY IN STRENGTH. GFS CONTINUE TO BE THE
UNFAVORED MODEL GIVEN FAR E OUTLIER...SO DON`T TRUST WAVEWATCH SEA
HEIGHTS AT THIS TIME. WILL CONTINUE WITH MARGINAL SCA BUT BUMPED
SEAS UP ABOUT A FOOT TO BETTER MATCH OUR OPC OFFSHORE FCST. AT
THIS TIME FCST HIGHLY DEPENDANT ON SYSTEM POTENTIAL DEVELOPMENT
WHICH IS BEING MONITORED BY NHC. WILL HOLD OFF ON ANY HEADLINES
GIVEN UNCERTAINTY WITH DEVELOPING LOW
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Quoting 7544:
could 92l at a 280 heading at this hour hmmm


275-285
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08/26/2009 02:04PM 2,113 invest_RENUMBER_al922009_al052009.ren
Member Since: September 23, 2005 Posts: 14 Comments: 11157
68. 7544
could 92l at a 280 heading at this hour hmmm
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Member Since: September 6, 2007 Posts: 0 Comments: 6485

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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.