Danny weakens further; 94L worth watching

By: Dr. Jeff Masters , 1:54 PM GMT on August 28, 2009

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Tropical Storm Danny continues to weaken, and may merely be a tropical depression. Data from the Hurricane Hunters early this morning showed top winds of just 40 mph at the surface, and satellite intensity estimates of Danny's strength are now rating the storm a tropical depression. Danny looks very disorganized on satellite imagery (Figure 1), with the low-level circulation center exposed to view. There is no heavy thunderstorm activity near Danny's center, and only a small area of heavy thunderstorms lying several hundred miles east of the center.


Figure 1. Morning satellite image of Danny, showing the exposed swirl of clouds where Danny's center is, well displaced from the heaviest thunderstorm activity to the east.

The forecast for Danny
With wind shear at 15 knots this morning, and forecast to increase to 20 knots tonight and 30 knots Saturday morning, is is unlikely Danny will be able to strengthen to more than a 50 mph tropical storm. Dry air from the upper-level low that has been keeping Danny disorganized continues to be a problem for the storm, as well. The GFDL and HWRF models continue to insist Danny will strengthen to a strong tropical storm or weak Category 1 hurricane, but this seems very unrealistic given Danny's current struggles. With Danny's heavy thunderstorms all on the east side of the storm, it is unlikely that New England will feel tropical storm force winds from Danny when it scoots past on Saturday. Large swells from Danny creating high surf along the beaches of New England will be the primary hazard from the storm.

Massachusetts hurricane history
Two tropical storms have affected Massachusetts in the past decade, though neither of these storms brought sustained winds of tropical storm force (39 mph) to the state. Tropical Storm Beryl of 2006 just missed Cape Cod as a weak tropical storm with 45 mph winds. Beryl brought wind gusts to tropical storm force to Nantucket Island, and a 1 foot storm surge. Tropical Storm Hermine hit southeast Massachusetts on August 31, 2004, as a minimum-strength tropical storm with 40 mph winds. No land stations in Massachusetts reported tropical storm force winds during Beryl. The last time Massachusetts measured tropical storm force winds was in 1991 during Hurricane Bob, which hit Rhode Island as a Category 2 hurricane. Provincetown, Massachusetts measured sustained winds of 98 mph, gusting to 115 mph, and Buzzard's Bay received a 15 foot storm surge.


Figure 2. Tropical wave 94L, a few hundred miles west of the Cape Verdes Islands.

Invest 94L
A well-organized tropical wave (94L) lies a few hundred miles west-southwest of the Cape Verdes Islands. This disturbance has shown little change this morning. This morning's QuikSCAT pass shows a complete circulation, elongated in the east-west direction, with top winds of 30 mph. Satellite imagery shows only a small amount of heavy thunderstorm activity near the circulation center, but considerable thunderstorm activity south of the center. Shear is low, about 10 knots, and is expected to remain low to moderate, 5 - 15 knots, over the next five days. The waters are warm enough to support development, 28°C, and are expected to remain in the 27 - 28°C range over the next five days. The dry Saharan Air Layer (SAL) lies about 200 miles to the north and west of 94L, and it appears from water vapor satellite imagery that a modest amount of dry air from the SAL is now being ingested into the storm, slowing development. Dry air will continue to slow development until 94L's heavy thunderstorm activity can moisten the atmosphere enough to shield the storm from the Saharan Air Layer. NHC is giving 94L a medium (30 - 50% chance) of developing into a tropical depression by Sunday. The GFDL and SHIPS models both predict 94L will be a Category 1 hurricane five days from now. However, the HWRF model does not develop 94L. Most of the models predict 94L will take a significant northward jog 3 - 5 days from now, in response to a strong trough of low pressure passing to the north (this is the same trough of low pressure that will be recurving Danny out to sea). It is then probable that 94L will be forced to the west again as the high pressure ridge steering the storm builds back in, and 94L will likely be a few hundred miles northeast of the Northern Lesser Antilles Islands seven days from now.

I'll have an update this afternoon.

Jeff Masters

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Link
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Take it with a grain of salt, as it is the HWRF (the biased beast producer)...

But Mexico could be in trouble from 94E!

finally our weather service has said something about this years drought.

http://www.caycompass.com/cgi-bin/CFPnews.cgi?ID=10385031
Member Since: Posts: Comments:
Danny keeps moving west of the forcast points
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If Danny moved due north the OBX wouldnt be out of danger
Member Since: September 19, 2005 Posts: 2 Comments: 4251
Quoting surfsidesindy:
Is it possible for a WADL to be organized before it even gets to the Atlantic?



I believe one has been named before it emerged from Africa.
Member Since: July 20, 2008 Posts: 0 Comments: 2935
The following is a great link. Click 'on' in the upper right hand corner for radar, clouds, etc. The white arrows will take you where you need to go, or you can glick and drag to choose your position. So you'll see Danny, the models (and they're labelled if you hold your cursor over them); moving over to the right, you can see the entire northern section of Africa, and there's a strong new wave about to emerge - have a look:

Link
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PRESENT MOVEMENT...STATIONARY
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Quoting TampaSpin:
Just completed my Tropical Update if anyone would like to veiw.

Thank you.. for 'the whole story' there Tampaspin ! ! Nice!
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94L still orange on TWO

94E and 95E in Pacific have red on TWO
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314. bwat
wow ULL on its doorstep and Danny is stationary. What's up? I know Danny is a shallow system but I can not believe he's not feeling some effects of the ULL.
Member Since: August 18, 2009 Posts: 0 Comments: 353
313. JRRP
SLOW DEVELOPMENT OF THIS SYSTEM OVER THE NEXT COUPLE OF DAYS AS
IT MOVES GENERALLY WESTWARD AT AROUND 15 MPH.
Member Since: August 16, 2007 Posts: 0 Comments: 5995
I personally think they have NFI where the centre of Danny is.. or if it even has one?

Member Since: October 1, 2007 Posts: 81 Comments: 26511
Quoting bwat:
2pm is up at NHC.


where's IKE? when you need him..
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Should have worded that question different. At what point will Danny get into the jet stream?

Quoting bwat:
The Gulf stream is a narrow swath of warm waters that flow up the east coast from the Gulf of Mexico.
Member Since: July 20, 2007 Posts: 0 Comments: 41
Quoting popartpete:
Danny is looking healthier to me.


me too and i dont trust him
Member Since: April 26, 2006 Posts: 5 Comments: 3216
308. bwat
2pm is up at NHC.
Member Since: August 18, 2009 Posts: 0 Comments: 353
Is it possible for a WADL to be organized before it even gets to the Atlantic?

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by the look of things in the atlantic and the waves of the coast of africa, wee might be in a heep of trouble in the next coming week..lets hope for the best.

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Quoting OracleDeAtlantis:
This is the craziest little storm I've seen in years. Early this A.M., it appeared to be forming a new center, but now I'm not sure. It's like the Energizer Bunny in a tug of war. It keeps going and going, and ...



[Source]
Danny is looking healthier to me.
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304. bwat
Quoting jaxbeachbum:
Is Danny close to the jet stream? Trying to learn. TIA

The Gulf stream is a narrow swath of warm waters that flow up the east coast from the Gulf of Mexico.
Member Since: August 18, 2009 Posts: 0 Comments: 353
299. yeah, i've been keeping an eye on that one for some time.
Member Since: September 14, 2007 Posts: 3 Comments: 3963
301. will40
5:37 PM GMT on August 28, 2009
Link

Pier cam for Emerald Isle NC should be interesting tomorrow
Member Since: September 19, 2005 Posts: 2 Comments: 4251
299. Grothar
5:36 PM GMT on August 28, 2009
Thanks Orca and pearlandaggie for those links.

Really good shots. Do not want to be premature, but that one wave looks mighty impressive, don't you think? I know they often fall apart, but it already has a good spin to it.
Member Since: July 17, 2009 Posts: 71 Comments: 26546
298. jaxbeachbum
5:35 PM GMT on August 28, 2009
Is Danny close to the jet stream? Trying to learn. TIA

Quoting will40:
With Danny i think we are seeing what the gulf stream waters can do for a system
Member Since: July 20, 2007 Posts: 0 Comments: 41
297. OracleDeAtlantis
5:34 PM GMT on August 28, 2009
This is the craziest little storm I've seen in years. Early this A.M., it appeared to be forming a new center, but now I'm not sure. It's like the Energizer Bunny in a tug of war. It keeps going and going, and ...



[Source]
Member Since: August 27, 2009 Posts: 0 Comments: 525
296. atmoaggie
5:32 PM GMT on August 28, 2009
I see Patrap has been about. Noticeably absent lately...
Hi Pat.
Member Since: August 16, 2007 Posts: 6 Comments: 12463
295. Murko
5:32 PM GMT on August 28, 2009
Quoting CaneHunter031472:


You bet!!


You're joking, right?
Member Since: July 13, 2007 Posts: 0 Comments: 155
294. pearlandaggie
5:32 PM GMT on August 28, 2009
Member Since: September 14, 2007 Posts: 3 Comments: 3963
293. K8eCane
5:32 PM GMT on August 28, 2009
NHC site loadin slow for anybody else?
Member Since: April 26, 2006 Posts: 5 Comments: 3216
292. K8eCane
5:31 PM GMT on August 28, 2009
Quoting leftovers:
thought danny would of got picked up by now being so close to the ull


i dont trust danny
Member Since: April 26, 2006 Posts: 5 Comments: 3216
291. OSUWXGUY
5:31 PM GMT on August 28, 2009
Quoting nrtiwlnvragn:


I'm looking at the increased image number visual loop and the low level clouds to the east of the exposed center. They appear to be pulled eastward. We should know within an hour or two, recon is approaching the system.


I can't get this to load for whatever reason. The Java starts and then nothing...

I haven't looked at the Rapid Scan 1 minute images, but have looked at the most recent available 15 from Rammsdis and still maintain the primary circulation... The last few frames the CoC starts getting stretched ever so slightly northwest-southeast.

And you're right...the Recon data will be the final word on what is going on under those clouds.
289. pearlandaggie
5:29 PM GMT on August 28, 2009
Member Since: September 14, 2007 Posts: 3 Comments: 3963
288. will40
5:28 PM GMT on August 28, 2009
Link link for African coast
Member Since: September 19, 2005 Posts: 2 Comments: 4251
287. K8eCane
5:26 PM GMT on August 28, 2009
rutrow
danny lookin better
Member Since: April 26, 2006 Posts: 5 Comments: 3216
286. Orcasystems
5:25 PM GMT on August 28, 2009
Quoting Grothar:


Nice little wave over Africa. Could be a little more activity than we all believed. Can anyone post a full view of the African Continent so we could see what else may be lurking? Couldn't find one


Member Since: October 1, 2007 Posts: 81 Comments: 26511
285. Grothar
5:23 PM GMT on August 28, 2009


Nice little wave over Africa. Could be a little more activity than we all believed. Can anyone post a full view of the African Continent so we could see what else may be lurking? Couldn't find one
Member Since: July 17, 2009 Posts: 71 Comments: 26546
284. pearlandaggie
5:20 PM GMT on August 28, 2009
LMAO @ 265! brilliant!
Member Since: September 14, 2007 Posts: 3 Comments: 3963
283. pearlandaggie
5:19 PM GMT on August 28, 2009
bye tig!
Member Since: September 14, 2007 Posts: 3 Comments: 3963
282. pearlandaggie
5:19 PM GMT on August 28, 2009
279. gotta be one of those mean, Australian saltwater crocs! LOL
Member Since: September 14, 2007 Posts: 3 Comments: 3963
281. pearlandaggie
5:18 PM GMT on August 28, 2009
Member Since: September 14, 2007 Posts: 3 Comments: 3963
280. WINDSMURF
5:18 PM GMT on August 28, 2009
Quoting presslord:
Attention all hands!!!

Do not expect any further updates or other communication from the NHC today...

...they have their hands full with JFVWS...

please do not awake the monster
Member Since: August 10, 2009 Posts: 0 Comments: 167
279. yonzabam
5:17 PM GMT on August 28, 2009
Is it an alligator or a crocodile? I can never remember what the difference is.


Member Since: July 20, 2008 Posts: 0 Comments: 2935
278. tiggeriffic
5:17 PM GMT on August 28, 2009
ok...gotta bounce...work to do, and gotta go get a futon for my oldest to sleep on when he gets here...peewee will be shocked, we haven't told him yet...he's been missing his big bro bad since he moved back in January...
Member Since: September 16, 2007 Posts: 0 Comments: 3650
277. will40
5:16 PM GMT on August 28, 2009
With Danny i think we are seeing what the gulf stream waters can do for a system
Member Since: September 19, 2005 Posts: 2 Comments: 4251
275. pearlandaggie
5:15 PM GMT on August 28, 2009
Member Since: September 14, 2007 Posts: 3 Comments: 3963
274. bwat
5:14 PM GMT on August 28, 2009
Quoting OSUWXGUY:


I'm going to respectfully disagree...

There is a long arc of clouds feeding into the convection from the southwest into the convection and arcing off to the northwest out of the northern part of the convection.

The low level circulation as a whole looks better/more round than it has been in quite a while...if not its entire life.

RGB Loop


I was thinking the same thing but did not want to be accused of wishcasting, but yes the circulation looks better know than when they hd it at 60mph.
Member Since: August 18, 2009 Posts: 0 Comments: 353

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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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