Ana and TD 3 take aim at the Lesser Antilles

By: Dr. Jeff Masters , 4:17 PM GMT on August 15, 2009

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Tropical Storm Ana was born this morning, when the remnants of Tropical Depression Two made a comeback and organized into the first tropical storm of the 2009 Atlantic hurricane season. Ana is the latest first named storm of the season since Hurricane Andrew got its name on August 17, 1992. The two storms have some similarities, as Andrew formed in the same part of the ocean, and also struggled in its early days with high wind shear and dry air. Let's hope the similarities end there.

Ana is struggling this afternoon. After an modest burst of heavy thunderstorm activity prompted NHC to upgrade Ana to a tropical storm early this morning, Ana has run into strong upper-level winds from the west that are creating high wind shear. This shear was not forecast, and it is not clear how long it will last. The shear has acted to drive dry air into the core of Ana, destroying almost all of Ana's heavy thunderstorms. The low-level center of the storm is now exposed to view, something that often foreshadows the death of a storm. It is possible the shear will destroy Ana, and several models (the GFS and ECMWF) forecast this may be the case. However, the shear forecast calls for shear to drop into the low range, 5 - 10 knots, tonight through Tuesday. If the shear does drop as forecast, Ana should be able to moisten the atmosphere around it sufficiently to protest itself from the dry Saharan air that surrounds it (Figure 1). SSTs are 27°C today, and will increase to 28°C by Sunday. By the time Ana moves into the Bahamas, total ocean heat content rises steeply (Figure 2), and rapid intensification of Ana is possible, if the shear and dry air haven't disrupted the storm. The intensity forecast models, for the most part, predict a steady intensification of Ana to the threshold of hurricane strength five days from now. The HWRF model is on the strong side, predicting a Category 2 hurricane. The GFDL predicts a weak tropical storm five days from now, but that is because the model has Ana passing over the rugged terrain of Hispaniola, something the other models do not predict. In summary, the intensity forecast for Ana has higher than usual uncertainty, and I give equal chances that the storm will be a hurricane--or non-existent--four days from now.


Figure 1. Water vapor image from this morning showing the large area of dry, Saharan air surrounding Ana, and lying to the north of Tropical Depression Three. Image credit: NOAA/SSD

Tropical Depression Three forms, could be Bill later today
QuikSCAT data from this morning and satellite loops revealed that the tropical wave (90L) in the middle Atlantic has finally developed a well developed surface circulation and can be classified as Tropical Depression Three. Recent satellite imagery suggests that TD 3 may already be Tropical Storm Bill. Water vapor imagery (Figure 1) shows that TD 3's center consolidated a few hundred miles south of the dry air of the Saharan Air Layer (SAL). Thus, the storm should not be affected by dry air and dust as much as Ana has been. Ana may also act to moisten the atmosphere in front of TD 3, helping protect the storm from the SAL as it edges farther north over the the three days.



Figure 2. Heat content of the ocean, in kJ per square cm. Oceanic heat content steadily increases for Ana and TD 3 as they approach the Lesser Antilles Islands. Oceanic heat content levels of 90 kJ per square cm are frequently associated with rapid intensification of hurricanes. Image credit: University of Miami.

Wind shear is moderate, 15 knots, but is forecast to fall to 10 - 15 knots on days 2 - 5. Sea Surface Temperatures are about 27.5°C, and will remain in the 27.5 - 28°C range the next five days. The combination of low wind shear and sufficiently warm SSTs should allow TD 3 to intensify steadily, and I expect the storm will be at hurricane strength by Wednesday, when it will be near the northern Lesser Antilles Islands. Most of our reliable intensity models strengthen TD 3 into a hurricane by Wednesday. Oceanic heat content (Figure 2) increases sharply just before the islands, so TD 3 could be intensifying rapidly as it moves through or just north of the Lesser Antilles on Thursday. TD 3 consolidated farther south than expected, so the track models calling for a more northerly path were probably incorrect. In particular, the ECMWF model, which had TD 3 turning sharply northwestward and missing the Lesser Antilles Islands, was probably much too far to the north in this morning's 00Z run. TD 3 will probably pass very close to the northern Lesser Antilles islands on Wednesday and Thursday.

I'll have an update Sunday.

Jeff Masters

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Hey everyone. Just woke up and saw probable Claudette coming into my friends in the Panhandle/Alabama regions. Good luck and stay safe later today!
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Tallahassee, FL TROPICAL CYCLONE IMPACTS webpage. They should soon have some info up, right now... nothing
Member Since: September 23, 2005 Posts: 14 Comments: 11281
Quoting jasoniscoolman10:
WATCH OUT N.C AND NORTH.


We worked that out.
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4261. IKE
Quoting IpswichWeatherCenter:


They won't mention it on the TV, its too late to evacuate people however there website is taking years to load:

http://www.wjhg.com/unclassified/769277.html

http://www.wjhg.com/


I didn't even think about evacuations.

East winds already here about 10 mph.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
No one.....and NOTHING. What a trip
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Quoting BajaALemt:
I just checked 7's website.....not even a banner


http://www.weather.com/weather/local/USFL0392?x=0&lswe=Panama+City&lswa=WeatherLocalUndeclared&y=0

Nothing... just - winds up to 30mph and heavy thunderstorms.
Member Since: Posts: Comments:
You guys want to know what's really funny? NWS in Tallahassee (which covers Gulf, Bay, and Walton Counties) doesn't even have a TSW up :)) :))
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4257. cjnew
thats good to hear Baja!
Yeah I wouldn't have thought we'd be first. hopefully it doesn't bomb out on us and just stays a TS.
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Here's the Image for all of you who are in Claudette's path (might as well call it that since its over hot water)

I'm off to bed good luck IKE lets hope they wake up =D
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Well, who'da thunk we'd be first under the gun...LOL!
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4253. HadesGodWyvern (Mod)
wait why do I hear music
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I'm out of it too, cj. I'm about a couple of blocks north of north lagoon.
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Fox 28 looks like it is starting to gear up for Soon-to-be Claudette

http://www.fox28.com/global/Category.asp?c=162708
http://www.fox28.com/global/Story.asp?S=10754383

Those two have only just turned up on there website.
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4250. drj27
isnt it getting closer to gain alot of strength correct me if im wrong
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4249. HadesGodWyvern (Mod)
hums to song playing
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At least it's moving quick. Less time over hot waters, and less time to flood places out.
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Quoting BajaALemt:
Hush! @ storse being crazy! I work at Winn-Dixie...I hope they all go to walmart!! LOL!!


Sorry! I'll tell everyone I know to go to WalMart for their supplies today! lol! :)
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I just checked 7's website.....not even a banner
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4245. cjnew
I'm over the bridge in town Baja, im out of the surge zones :D lol
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well heres whats feeding "Claudette"...
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Hush! @ storse being crazy! I work at Winn-Dixie...I hope they all go to walmart!! LOL!!
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Quoting IKE:
Bastardi was calling for this....stormno was, but he thought it would head to LA.

There are others...TampaSpin.....

Channel 7 in Panama City hasn't even mentioned it....hello! Wake up. lol


They won't mention it on the TV, its too late to evacuate people however there website is taking years to load:

http://www.wjhg.com/unclassified/769277.html

http://www.wjhg.com/
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Quoting IKE:
Channel 13 in Panama City....nothing....

FOX 28 in Panama City...nothing...



Long time lurker here. I'm in Mobile and I've checked all the local news stations this morning as well....nothing here either (with the exception of a mention to watch it on wkrg.com). It's amazing to me that this can happen. Hope it's very small and weak so that it doesn't catch anyone unprepared....the stores will be crazy today. Good thing we picked up some stuff yesterday just in the event that 'Gulf Blob' flared up!!
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4240. IKE
Quoting BajaALemt:
LOL Ike! I think this caught a whole lot of folks.....ummmm, in this case....sleeping


Literally....
Member Since: June 9, 2005 Posts: 23 Comments: 37860
You east end or west end, cj? I'm down on the east end
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Quoting IKE:
Channel 13 in Panama City....nothing....

FOX 28 in Panama City...nothing...



Like I said they need the hot coffee spilt on them it isn't working by just drinking it LOL =D
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4236. IKE
Quoting neonlazer:

The meteorologist is sleeping!..he must not be awaken..though id think someone is in the office..at least they could page him and tell him to get the heck out of bed..haha


LOL...

Buoy within 50 miles of the COC...not much...but it's WNW of the center....
Member Since: June 9, 2005 Posts: 23 Comments: 37860
LOL Ike! I think this caught a whole lot of folks.....ummmm, in this case....sleeping
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4234. cjnew
Quoting IKE:
Channel 13 in Panama City....nothing....

FOX 28 in Panama City...nothing...

Im telling you Ike no one has a clue down here! :/
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Quoting neonlazer:


Does it seem it looks less organized on radar?..or do i need to get some sleep, haha.


TD 4 - is consolidating.

Its amazing that you go to bed at 22:00 BST, and get up at 10:41 BST - and this just decides to turn up.
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Quoting IKE:
Channel 13 in Panama City....nothing....

FOX 28 in Panama City...nothing...


The meteorologist is sleeping!..he must not be awaken..though id think someone is in the office..at least they could page him and tell him to get the heck out of bed..haha
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im awake the grandbaby got me up
but i knew when i went to bed we would have a td if not a ts this morning.. had to have a little sleep.....
so im sitting here working on my shopping list since this was my prep week.... watching ana and bill... and along comes td4 to celebrate the 40th aniv of camile..... yep thats monday....
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4230. IKE
Channel 13 in Panama City....nothing....

FOX 28 in Panama City...nothing...

Member Since: June 9, 2005 Posts: 23 Comments: 37860
Hmm, I was hoping it would head towards Louisiana-ish. Need some rain here. :p
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4228. IKE
Quoting BajaALemt:
Yay...I get off of work at 1:30 this afternoon so i'll get to watch it come in.


Probably a 50-60 mph TS at landfall.

Coming in from our SSE may lessen it's affects...hopefully....
Member Since: June 9, 2005 Posts: 23 Comments: 37860
Quoting IKE:
Bastardi was calling for this....stormno was, but he thought it would head to LA.

There are others...TampaSpin.....

Channel 7 in Panama City hasn't even mentioned it....hello! Wake up. lol


Wow! LOL like a said earlier rude awakening. Maybe they should have some of that coffee dumped on them it isnt working fast enought hehe
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Yay...I get off of work at 1:30 this afternoon so i'll get to watch it come in.
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4225. IKE
Claudette is imminent...within hours....
Member Since: June 9, 2005 Posts: 23 Comments: 37860
4224. IKE
Bastardi was calling for this....stormno was, but he thought it would head to LA.

There are others...TampaSpin.....

Channel 7 in Panama City hasn't even mentioned it....hello! Wake up. lol
Member Since: June 9, 2005 Posts: 23 Comments: 37860
Quoting drj27:
so its going to make landfall in pc correct




maybe?
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4221. HadesGodWyvern (Mod)
sure those that have weather radio got awaken with a startle
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4220. cjnew
hahaha yes that's probably a close description of what it'll be like.
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4219. IKE
Quoting drj27:
so anyone think it could get to hurricane strength


I wouldn't rule it out.
Member Since: June 9, 2005 Posts: 23 Comments: 37860
4218. drj27
so its going to make landfall in pc correct
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Quoting drj27:
so anyone think it could get to hurricane strength

I think NHC had it at like 1% chance lol..not likely..
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Quoting drj27:
so anyone think it could get to hurricane strength


NHC doesn't just yet on the site but hey anything can happen examples are Humberto 07 and Marco 08 (not a hurricane but a strong TS)
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4215. TxKeef
I'm debating on calling and waking him up to let him know, cause I'm pretty sure he has no idea. He lives probably 100 yards from the water in destin
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4214. drj27
so anyone think it could get to hurricane strength
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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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