Disturbance 90L close to tropical depression strength; TD 2 may rise again

By: Dr. Jeff Masters , 2:02 PM GMT on August 14, 2009

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A strong tropical wave (90L), with a large circulation and a moderate amount of heavy thunderstorm activity, is a few hundred miles southwest of the Cape Verdes Islands, off the coast of Africa. This morning's QuikSCAT pass shows that 90L has a large circulation, but this circulation is not yet well-formed, as it is elongated along an east-west axis. Satellite imagery from the European METEOSAT satellite show that the heavy thunderstorms associated with 90L are gradually becoming better organized, with some spiral banding evident on the south side of the storm. Satellite intensity estimates from NOAA already put 90L at tropical depression strength with 30 mph winds, but the storm does not yet have a well enough formed circulation to be classified as a depression. Water vapor imagery shows that since 90L is forming several hundred miles south of the dry air of the Saharan Air Layer (SAL), the storm should not be affected by dry air and dust as much as Tropical Depression Two was. However, there is some dry air from the SAL being sucked into the circulation of 90L, and this is retarding its development.

Wind shear is moderate, about 10 - 15 knots, but is forecast to fall to the low range, 5 - 10 knots, later today. Shear is then forecast to remain low for the next five days. Sea Surface Temperatures are about 28°C, and will remain in the 27 - 28°C range the next five days. The combination of low wind shear and sufficiently warm SSTs should allow 90L to develop into a tropical depression by Saturday, and potentially reach hurricane strength by Wednesday. Most of our reliable models strengthen 90L into a hurricane by Wednesday, when the storm is expected to be near the northern Lesser Antilles Islands. One important outlier is the ECMWF model, which has 90L passing to the north of the islands, and eventually recurving out to sea east of Bermuda. The ECMWF was by far the most reliable model for forecasting hurricane tracks last year. However, all of our models are pretty unreliable going out 5 days in advance for systems that have yet to reach tropical depression strength. Once 90L becomes a tropical depression and develops a well-formed circulation, the models will have a better handle on forecasting where it will go.


Figure 1. The remnants of Tropical Depression Two (left side of image) and tropical wave 90L (right side of image).

Tropical Depression Two may come back
Tropical Depression Two died yesterday, but may rise again. Satellite loops of the remnants of the storm show that heavy thunderstorms are again attempting a comeback near the axis of what is now a tropical wave. However, dry air continues to interfere with the development of the thunderstorm activity, and moderately high wind shear of 15 - 20 knots is also inhibiting the process. Wind shear over the remnants of TD 2 is expected to remain in the moderate range, 10 - 20 knots, over the next four days. Sea Surface Temperatures (SSTs) are 27°C, but will warm to 28°C two days from now. There is plenty of dry, stable air from the Saharan Air Layer (SAL) to the north and west that will continue to cause the storm problems. The relatively cool SSTs and dry air mean that any re-development of the storm will be slow to occur. NHC has given the system a medium (30 - 50% chance) of becoming a tropical depression again by Sunday morning. Only one reliable model, the NOGAPS, is predicting regeneration of TD 2. The NOAA Hurricane Hunters are flying research missions into the remnants of TD 2 today and Saturday.

I'll have an update Saturday morning, or earlier, if significant developments occur.

Jeff Masters

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Td2 isn't looking too bad right now structure wise
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983. JLPR
90L appears to be spinning better today
but it lacks convection over the center
come on shear! xD
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Is that model taking a hurricane into Florida and then into the panhandle??? Or are my eyes just crossed.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Quoting jeffs713:

GFS - everyone is freaking about what is now 90L hitting SE FL.
GFDL - cat 3 in 5-7 days north of the islands
HWRF - Apocolyptocane north of Hispaniola in 7-ish days.

T#s:
Not sure about former TD2.
90L is still at 1.0/1.0.

The blog:
A third the blog is freaking out about the GFS model.
JFV/WS is already worried.
A third of the blog is laughing at the first third.
The final third of the blog is actually talking about pertinent tropical stuff.


T numbers for 90L is 1.5/1.5.
Member Since: August 10, 2009 Posts: 3 Comments: 672
Lol look at this!

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Quoting 7544:
2. CaneWarning 6:32 PM GMT on August 14, 2009 Hide this comment.

Quoting extreme236:


I like your graphic posts.



So do I and they aren't causing my computer any problems at all.
Action: Quote | Ignore User
dont get me wrong i love them too its great info but when im on ie it frezzes the comp 3 times on every page he post them when he post without all is fine but fire fox is fine just on ie and thats what i like to use here . thanks
This site has plenty of features to allow users to filter content to suit their individual tastes/needs. It is my opinion that these features would be of use to some here today. Please try them and there will be no need for you to attempt to shape the content of a VERY popular blog to suit your individual situation.
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Adrian

What does the ECMWF make up of EX02L?
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Quoting 7544:
2. CaneWarning 6:32 PM GMT on August 14, 2009 Hide this comment.

Quoting extreme236:


I like your graphic posts.



So do I and they aren't causing my computer any problems at all.
Action: Quote | Ignore User
dont get me wrong i love them too its great info but when im on ie it frezzes the comp 3 times on every page he post them when he post without all is fine but fire fox is fine just on ie and thats what i like to use here . thanks and with all promblems we and drake had it good to post whats happening

Install "NoScript" on firefox, it helps. It is found found in the "addons" option on your menu bar.
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SHIPS making TD2 a decent hurricane.
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Quoting hurricane23:


Keep in mind the longer this thing 90L takes to develope the futher west it will come before it gains any real laltitude.As of right now its being impacted by easterly shear but its still holding its own.I think this will go ahead and become a depression 2morrow.


I agree, even if there is a strong trough, timing is crucial.
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Last 3 hours of readings from ADT: (None updated since 1645UTC)

2009AUG14 134500 1.0 1014.0/ +0.0 / 25.0 1.0 1.0 1.0 NO LIMIT ON OFF 18.94 14.09 SHEAR N/A 14.39 40.70 EXTRP
2009AUG14 141500 1.0 1014.0/ +0.0 / 25.0 1.0 1.0 1.0 NO LIMIT OFF OFF 18.54 13.58 SHEAR N/A 14.40 40.77 EXTRP
2009AUG14 144500 1.0 1014.0/ +0.0 / 25.0 1.0 1.0 1.0 NO LIMIT OFF OFF 17.84 13.28 SHEAR N/A 14.41 40.84 EXTRP
2009AUG14 151500 1.0 1014.0/ +0.0 / 25.0 1.0 1.0 1.0 NO LIMIT OFF OFF 18.44 13.23 SHEAR N/A 14.39 40.91 EXTRP
2009AUG14 154500 1.0 1014.0/ +0.0 / 25.0 1.0 1.5 2.0 0.5T/hour OFF OFF 18.64 13.05 SHEAR N/A 14.39 40.98 EXTRP
2009AUG14 161500 1.1 1013.6/ +0.0 / 25.0 1.1 1.5 1.8 0.5T/hour OFF OFF 19.04 12.29 SHEAR N/A 14.40 41.05 EXTRP
2009AUG14 164500 1.2 1013.2/ +0.0 / 25.0 1.2 1.5 1.9 0.5T/hour OFF OFF 19.14 8.65 SHEAR N/A 14.41 41.12 EXTRP
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Quoting jeffs713:

GFS - everyone is freaking about what is now 90L hitting SE FL.
GFDL - cat 3 in 5-7 days north of the islands
HWRF - Apocolyptocane north of Hispaniola in 7-ish days.

T#s:
Not sure about former TD2.
90L is still at 1.0/1.0.

The blog:
A third the blog is freaking out about the GFS model.
JFV/WS is already worried.
A third of the blog is laughing at the first third.
The final third of the blog is actually talking about pertinent tropical stuff.



hahahaha, that's funny!
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Visible animation of out tiny spec and 90L which is coming into the picture.

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Quoting FloridaTigers:
I'v been at work today, whats new? Models? T#'s?

GFS - everyone is freaking about what is now 90L hitting SE FL.
GFDL - cat 3 in 5-7 days north of the islands
HWRF - Apocolyptocane north of Hispaniola in 7-ish days.

T#s:
Former TD2 is 1.0/1.0.
90L is still at 1.5/1.5.

The blog:
A third the blog is freaking out about the GFS model.
JFV/WS is already worried.
A third of the blog is laughing at the first third.
The final third of the blog is actually talking about pertinent tropical stuff.
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Quoting HurricaneKyle:


No where near 30kts. 10-15 knots. If your talking about 90L that is.


I deleted that post because I realized that the vorticity was from 11AM EDT...and so was only moderately off center...


Ok so between 20-30 knots of shear depending on the part of the circulation you're looking at. Greenish-Yellow to Yellow on the linked image below where 90L is - 12N 29W

Decreasing trend though...

Shear Tendency
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000
WHXX01 KWBC 141836
CHGHUR
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1836 UTC FRI AUG 14 2009

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO NHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

ATLANTIC OBJECTIVE AIDS FOR

DISTURBANCE TWO (AL022009) 20090814 1800 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
090814 1800 090815 0600 090815 1800 090816 0600

LAT LON LAT LON LAT LON LAT LON
BAMS 14.7N 43.2W 15.2N 45.2W 16.1N 48.0W 17.4N 51.8W
BAMD 14.7N 43.2W 15.4N 45.5W 16.5N 48.2W 17.6N 51.3W
BAMM 14.7N 43.2W 15.1N 45.3W 15.9N 48.0W 16.6N 51.2W
LBAR 14.7N 43.2W 15.1N 45.7W 15.8N 48.8W 16.8N 52.2W
SHIP 25KTS 30KTS 37KTS 43KTS
DSHP 25KTS 30KTS 37KTS 43KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
090816 1800 090817 1800 090818 1800 090819 1800

LAT LON LAT LON LAT LON LAT LON
BAMS 19.3N 56.2W 23.3N 64.9W 27.0N 70.9W 29.4N 73.4W
BAMD 18.8N 54.7W 21.1N 61.9W 23.7N 68.0W 24.9N 71.5W
BAMM 17.5N 55.1W 19.5N 63.6W 21.9N 71.3W 24.0N 77.0W
LBAR 17.8N 55.9W 20.3N 63.4W .0N .0W .0N .0W
SHIP 51KTS 65KTS 71KTS 76KTS
DSHP 51KTS 65KTS 71KTS 76KTS

...INITIAL CONDITIONS...
LATCUR = 14.7N LONCUR = 43.2W DIRCUR = 275DEG SPDCUR = 15KT
LATM12 = 14.4N LONM12 = 40.1W DIRM12 = 277DEG SPDM12 = 12KT
LATM24 = 14.2N LONM24 = 37.9W
WNDCUR = 25KT RMAXWD = 40NM WNDM12 = 25KT
CENPRS = 1007MB OUTPRS = 1010MB OUTRAD = 150NM SDEPTH = M
RD34NE = 0NM RD34SE = 0NM RD34SW = 0NM RD34NW = 0NM

$$
NNNN


Now up to hurricane strength.
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Quoting leftovers:
after hugo some people turned into savages on the american virgin islands. better get the national guard ready


My sister was on St. Thomas for Hugo. Then she was on the first plane out after Marilyn in 1995. She said NEVER again. The hurricane is one thing but the aftermath is hell.
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Quoting reedzone:


Its not caused by posts, someone is planting a virus that slows the blog completely and freezes it, happens alot to me. Whoever it is, needs to come forth and confess.


Listen sport,If the Malware is embedded in a Ad Banner ,or a Page Load,its not gonna be a Human jumping up and Confessing to you Like your the Maker..get a grip..unplug from the web and do a Virus scan,.
I suggest AVG,or other good one
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Quoting mobilegirl81:
WE INTERRUPT THIS TROPICAL STUATION FOR A SPECIAl REPORT!!!!!: storm stories lol!
LOL
Ok MissWeatherChannel. : )
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I can tell the blog will be total choas before this storm even gets a name.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
960. 7544
2. CaneWarning 6:32 PM GMT on August 14, 2009 Hide this comment.

Quoting extreme236:


I like your graphic posts.



So do I and they aren't causing my computer any problems at all.
Action: Quote | Ignore User
dont get me wrong i love them too its great info but when im on ie it frezzes the comp 3 times on every page he post them when he post without all is fine but fire fox is fine just on ie and thats what i like to use here . thanks and with all promblems we and drake and patrap had it good to post whats happening
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we might need the National Guard in here soon...lol
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Quoting reedzone:


Hey Adrian, getting more interesting, does it show an East Coast event or out to sea? I'm not a paid member so I didn't see it yet.


Keep in mind the longer this thing 90L takes to develope the futher west it will come before it gains any real laltitude.As of right now its being impacted by easterly shear but its still holding its own.I think this will go ahead and become a depression 2morrow.
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I'v been at work today, whats new? Models? T#'s?
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Thanks, Patrap! I'll definitely check that out!
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Taiwan's President in hot water in response to Morakot...

Taiwan's president criticized for typhoon response- By PETER ENAV, Associated Press
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Do you REALLY feel safe behind that wood?


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Quoting 7544:


hi thanks its not just me now its from post 858 ID IS P451 he did thuis on 3 other pages and everytime he post those 3 images everything frezzes SO HE OR SHE MUST LINK THEM ITS HAPPEN THREE TIMES ALL ON DIF PAGES ITS NOT FUNNY ANYMORE



Maybe A Pc check-up is in order ... no probs here at all with anything anyone post
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Quoting CaneWarning:


So do I and they aren't causing my computer any problems at all.


Its not caused by posts, someone is planting a virus that slows the blog completely and freezes it, happens alot to me. Whoever it is, needs to come forth and confess.
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I'm out until later
Member Since: August 19, 2006 Posts: 0 Comments: 15671
Quoting jlp09550:

I agree. I've seen my share of photoshopped images.
I'll say it looks shopped too. If you have the option or care enough to zoom in on the pic, it is pretty apparent that the splice is from the edge of the curtain/blinds to down below the tv table. All the insulation is bubbled into the splice of the 'before' portion which is the top left area.
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Quoting P451:


This system is unique in that it refuses to quit. It's been somewhat written off 3 or 4 times now. If you recall even before it was an invest it was going through the same cycles.


It is persistent if nothing else.
Member Since: August 19, 2006 Posts: 0 Comments: 15671
WE INTERRUPT THIS TROPICAL STUATION FOR A SPECIAl REPORT!!!!!: storm stories lol!
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Quoting hurricane23:
12z ECM again much further north but further southwest than then its 0z run.


Hey Adrian, getting more interesting, does it show an East Coast event or out to sea? I'm not a paid member so I didn't see it yet.
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Quoting extreme236:


I like your graphic posts.


So do I and they aren't causing my computer any problems at all.
Member Since: April 26, 2009 Posts: 3 Comments: 3667
Finally some systems for generating waves...looks like both Florida coasts will have something to look forward to.
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Quoting 7daysnopowerfrancis:
I drove through Arcadia on my way to Venice, FL to escape Hurricane Frances which was 3 weeks after Charley. Arcadia is about an hour inland, and their buildings were destroyed. Debris was piled 20 feet high by the curb.

It was eerily creepy as we were driving by it at 3 in the morning attempt to escape from a hurricane ourselves.


SUE! Long time no see honey! Miss you- hope all is well your way :)
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Quoting OSUWXGUY:
Huh?

Anyone look at the 850 vorticity from CIMSS???

How is that the core of the 850 vorticity is still back south of the Cape Verde Islands, when the satellite shows a huge rotating tenacled beast near 30W???

(admittedly under 30 knots of upper level easterly shear)

850 Vorticity View



No where near 30kts. 10-15 knots. If your talking about 90L that is.
Member Since: August 10, 2009 Posts: 3 Comments: 672
937. 7544
Quoting P451:


Okay, enough, I've explained to you twice the situation.

If you still have problems you can:

a) put me on ignore, and my posts won't show up for you.
b) talk to the administrator of the blog

Outside of this I cannot help you. I'm not going to stop posting because 1 user believes my posts are causing him problems.

No one else has complained. Many have said outright they have no problem.

You have your options, use them, and kindly stop yelling at me.



YES REDZONE ALSO HAS IT HES GETTING FRoze TO JUST LINK THEM i dont want any promblems nor does anyone else thanks
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Quoting VoodooRue:
New Orleans in the house, saying hello. Lurking constantly. Just wanted to thank everyone for their input and opinions. I value them greatly.



Welcome Local Lady.

Be sure to check this Date on the 22nd.

www.risingtidenola.net






AUG. 22, 2009, 9 a.m. - 4:45 p.m.
Register now by clicking the button below! Fee is $20 for preregistration. $30 on the day of the event.
Register before August 12th - $20.
Register between August 12th and August 20th - $25. Register after August 20th - $30.
Bring a guest with you to our Friday night meet and greet - $5.

Updated schedule of speakers and events is coming soon. Rising Tide is a gathering for all who wish to learn more and do more to assist New Orleans' recovery from the aftermath of Hurricanes Katrina and Rita, and the failure of the levees that were supposed to protect the area.
Harry Shearer

We will come together to dispel myths, promote facts, share personal testimonies, highlight progress and regress, discuss recovery ideas, and

promote sound policies at all levels. We aim to be a "real life" demonstration of internet activism as we continue to recover from a massive failure of government on all levels The conference will be held at Zeitgeist Multi-disciplinary Arts Center, 1724 Oretha Castle Haley Blvd (@ Felicity) New Orleans, LA 70113.

Blogger, entertainer and defender of New Orleans Harry Shearer will be keynote speaker at the Conference this year

Rising Tide started in the wake of Hurricane Katrina and the subsequent flooding of the city when a small group of New Orleans, La.-based bloggers decided to expand their on-line advocacy for the rebirth of New Orleans into a public event.
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Quoting P451:


Okay, enough, I've explained to you twice the situation.

If you still have problems you can:

a) put me on ignore, and my posts won't show up for you.
b) talk to the administrator of the blog

Outside of this I cannot help you. I'm not going to stop posting because 1 user believes my posts are causing him problems.

No one else has complained. Many have said outright they have no problem.

You have your options, use them, and kindly stop yelling at me.



I like your graphic posts.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
Quoting 7544:



HEY MAN PLEASE STOP POSTING THOSE THINGS YOU ARE FREZZING UP THE BLOG ON EVERYPAGE YOU PUT THEM TY

The ignore button is your friend. ;)
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About JeffMasters

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.