African Tropical Wave 98L Moving Over Cooler Waters

By: Dr. Jeff Masters , 2:23 PM GMT on July 23, 2013

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A strong and well-organized tropical wave that moved off the coast of Africa on Monday (98L) is located a few hundred miles south of the Cape Verde Islands and is moving west-northwest at 15 - 20 mph. Satellite images show that 98L has a decent amount of spin, but only a modest amount of heavy thunderstorms that have not changed much in intensity or areal coverage this morning. The wave is under a moderate 10 - 20 knots of wind shear, which will tend to allow slow development. A large amount of dry air lies to the north and west of 98L, and this dry air will likely interfere with development later this week. The SHIPS model predicts that wind shear will stay in the moderate range through Saturday. Ocean temperatures are barely adequate for development, about 26.5°C today, and will be below average over the region of ocean 98L will be traversing on Wednesday and Thursday, 25 - 26°C. These temperatures are very marginal for development. The Madden Julian Oscillation (MJO), a pattern of increased thunderstorm activity near the Equator that moves around the globe in 30 - 60 days, does not favor increased chances of Atlantic tropical cyclone formation this week. The reliable computer models for tropical cyclone genesis do not predict that 98L will develop this week. In their 8 am EDT Tuesday Tropical Weather Outlook, NHC gave 98L a 40% chance of developing into a tropical cyclone by Thursday. 98L should maintain a west-northwest track through the week, and may spread heavy rains and gusty winds to the northern Lesser Antilles Islands beginning on Saturday night or on Sunday.


Figure 1. Satellite image of 98L off the coast of Africa taken at 8 am EDT Tuesday July 23, 2013, with a satellite analysis of where dry air is, as well. A large amount of dry air lies to the north and west of 98L, and will likely interfere with development later this week. Image credit: University of Wisconsin CIMSS and NOAA/HRD.

Jeff Masters

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Quoting 2509. opal92nwf:
Kinda looks like an eye


It has lost weight since it emerge off Africa. Allowing it to deepen even with sst not supporting it. It still has a piece of energy to its east and south that will continually feed our system through those cool waters. After that it should really bulk up some and wrap that energy around it.
Member Since: May 25, 2012 Posts: 0 Comments: 2043
Quoting 2519. washingtonian115:
Talk about false advertising.lol


This one is better suited..

yeah anyway huh Wash do you understand the point I'm making
Member Since: June 13, 2009 Posts: 2 Comments: 12712
Dorian is amazing... haven't shown any hint of weakening even though it should be over cooler waters today and tomorrow. After that... I honestly believe Dorian could have a shot to become significant storm.

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Quoting 2519. washingtonian115:
Talk about false advertising.lol


This one is better suited..


We have had rain in Pensacola EVERY DAY since July 3.
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2524. KEEPEROFTHEGATE (Mod)
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Quoting 2453. washingtonian115:
Hmmm shows it having little land interaction and intensifying..Florida?.Lolol.
No thanks.
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2522. Grothar
Quoting 2508. padirescu:


You're right Grothar... Since there isn't such a thing as a 26 mile marathon. :-)

They're all 26.2 miles and as a marathoner those last .2 really hurt.


I couldn't never dream of making it that extra .2 miles. So essentially I NEVER could run a 26 mile marathon.
Member Since: July 17, 2009 Posts: 71 Comments: 27125
down goes the Waltanater....down goes the Waltanater....
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I see a few storm go to a hurricane under 76 water temp before
Member Since: March 12, 2013 Posts: 102 Comments: 100956
Talk about false advertising.lol


This one is better suited..
Member Since: August 14, 2010 Posts: 10 Comments: 17661
2518. KEEPEROFTHEGATE (Mod)
Quoting 2516. Grothar:


Oh, I believe it has a very strong possibility to hit the US mainland. That is what I have maintained from the beginning. What I did write is that I expect a weakness in the ridge to begin moving it further north after it reaches the islands, which is one scenario. But right now I do not possibly see it moving into the Caribbean.


ya it stays in the atlantic
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2517. FOREX
Quoting 2504. pensacolastorm:
Morning bloggers. Latest visible loop shows what looks like an eye for the not yet named TD4. I'm hoping for an unexpected and unlikely recurve to the north or a giant gulp of dry air.


Some bloggers are talking about a strenghthening Bermuda high while others are showing recurve cones of Earl. Confusing to me.
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2516. Grothar
Quoting 2486. VR46L:


I hope you are right , But I think its more of a possibility than the Euro Solution at the moment. if it has not Turned North before the Islands and is a storm there is no reason why a US landfall could not Happen .. Very strong High aint going to let it go north IMO


Oh, I believe it has a very strong possibility to hit the US mainland. That is what I have maintained from the beginning. What I did write is that I expect a weakness in the ridge to begin moving it further north after it reaches the islands, which is one scenario. But right now I do not possibly see it moving into the Caribbean.
Member Since: July 17, 2009 Posts: 71 Comments: 27125
2515. KEEPEROFTHEGATE (Mod)

2013 Storms




All

Active

Year




Atlantic


green ball04L.DORIAN



East Pacific


green ball98E.INVEST



Central Pacific



West Pacific


green ball98W.INVEST



Indian Ocean



Southern Hemisphere
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2514. KEEPEROFTHEGATE (Mod)
Tropical Depression 04L (FOUR) Warning #01
‎Today, ‎July ‎24, ‎2013, ‏‎6 minutes ago | CDO.FWC.NRFK.fct@navy.mil (FWC-N CDO)Go to full article
Issued: Wed 24 Jul 2013 06:00Z
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Quoting 2495. Grothar:


I will never run in a 26 mile marathon.
That's funny right there I tell ya :o)

Taco :o)
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2512. Skyepony (Mod)
Quoting 2485. SouthernIllinois:

Bet you really miss OLTL now since it's been off the air for two years. We're you a AMC fan too?

I miss it still. Atleast the Mannings have lived on at GH..

I had an Arabian mare named Dorian..


Check out the RAMMB NOAA site.. He's named Dorian there too..

WOW..click pic for loop.
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Work to do in the hurricane preparation dept.; gotta work on the generator...

Make sure you're prepared...

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Quoting 2490. CaribBoy:
EARL

Advisory 1


Advisory 18

Yep nearly the same day but not the same month and year, it could be an EARL's history maker.
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Kinda looks like an eye
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Quoting 2495. Grothar:


I will never run in a 26 mile marathon.


You're right Grothar... Since there isn't such a thing as a 26 mile marathon. :-)

They're all 26.2 miles and as a marathoner those last .2 really hurt.
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Quoting 2482. DataNerd:
Wind speeds are still increasing by the look of satellite imagery. Link
If I took a random glimpse at that shot without knowing what storm that was, I wouth think that it was either a strong TS or a hurricane.
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Quoting 2486. VR46L:


I hope you are right , But I think its more of a possibility than the Euro Solution at the moment. if it has not Turned North before the Islands and is a storm there is no reason why a US landfall could not Happen .. Very strong High aint going to let it go north IMO


Not sure about the Euro either its has actually moved more west since designation. With a predicted 600 DM High predicted it wont see 20N for quite some time.
Member Since: May 25, 2012 Posts: 0 Comments: 2043
2505. FOREX
Quoting 2490. CaribBoy:
EARL

Advisory 1


Advisory 18


Right now Dorians cone is much further south than what you are showing with Earl.
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Morning bloggers. Latest visible loop shows what looks like an eye for the not yet named TD4. I'm hoping for an unexpected and unlikely recurve to the north or a giant gulp of dry air.
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Just got up and am really surprised for not only how well organized this system is, but it's forecasted track. Sort of scary for S. Florida.
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Quoting 2476. washingtonian115:
Wunderkid I hate to put you down but this isn't headed for the Caymans.Sorry just isn't in Dorian's future..

lol your not PART OF COMMENT REMOVED BY WUNDERKIDCAYMAN I never said it was heading for cayman hell I never even mention the W Caribbean

I said what I said to make a point now wash PART OF COMMENT REMOVED BY WUNDERKIDCAYMAN can you figure out the point I'm making
Member Since: June 13, 2009 Posts: 2 Comments: 12712
Quoting 2456. mikatnight:


Post #2303 if you missed it. Some other pics from this morning in My Photos.
Mik...Judging by the photo I would say you are around the corner from the Old Key Lime House (bridge construction) I lived up the road from you until 2 months ago on South Palmway, lake Worth... I now live in West Boynton
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AL, 04, 2013072412, , BEST, 0, 140N, 290W, 45, 1002, TS, 34, NEQ, 40, 30, 0, 30, 1012, 150, 20, 55, 0, L, 0, , 0, 0, DORIAN, D,

4/0/0 7/24/13...Not bad 11 away from acheiving my tropical storm numbers.
Member Since: June 30, 2013 Posts: 12 Comments: 8774
Quoting 2478. Waltanater:
It's not official. NHC is the one that makes it official!


Yes, and the thing we are referring to comes from the NHC. The NHC has clearly labeled this Dorian.
Link
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Quoting 2491. Skyepony:

NAVY has declared it.. they used the name.. If this died in the water before NHC had a chance to declare it at 11 then the name is already used & the next name wouldn't be Dorian..

It won't die in 26 sea temperature but maintain intensity
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2495. Grothar
Quoting 2487. SouthernIllinois:

Never say never. An old timer like you should know that.


I will never run in a 26 mile marathon.
Member Since: July 17, 2009 Posts: 71 Comments: 27125
Quoting 2482. DataNerd:
Wind speeds are still increasing by the look of satellite imagery. Link


Hey things have change since you left Lol, in mere hours this has undergo rapid deepening. This might be one of the most interesting 11am advisory this season. And this will bring plenty more rain to an already soaked PR. If it gets close enough. And its still July.
Member Since: May 25, 2012 Posts: 0 Comments: 2043
2492. hydrus
Quoting 2439. Grothar:
The models are moving more WNW on each run. Well it looks like this may miss the Caribbean entirely.


I do not believe it will ever see Caribbean. 04L does remind me ( a Little ) of how Elena track across the Atlantic.

Wiki..The origins of Hurricane Elena can be traced to an easterly tropical wave that was first identified off the western coast of Africa on August 23, 1985. The system sped westward across the Atlantic at up to 35 mph (56 km/h). Its rapid motion, combined with the presence of an unusually hostile Saharan Air Layer, prevented tropical cyclogenesis for several days. Driven by a strong subtropical ridge to its north, the wave quickly approached North America as it began to show signs of organization. At 00:00 UTC on August 28, the disturbance developed into a tropical depression while over the Windward Passage. The newly designated depression began to track west-northwestward over Cuba, which is known to disrupt tropical cyclone development. Despite that, its central barometric pressure continued to deepen, and reconnaissance aircraft found winds exceeding 50 mph (80 km/h) near the center. In response, the National Hurricane Center upgraded the depression to Tropical Storm Elena over northern Cuba later on August 28.[2][3]

After passing north of Havana, Cuba, Elena emerged into the Gulf of Mexico. At 12:00 UTC on August 29, Elena intensified into a Category 1 hurricane.[3] Analysis of steering currents through the morning of August 30 suggested that Elena would continue on its northwestward track, striking the area between New Orleans, Louisiana, and Biloxi, Mississippi within 30 hours.[4] Unexpectedly, a mid-to-upper-level trough of low pressure diving in from the northwest created a weakness in the easterly currents, allowing Elena to recurve and slow drastically in forward speed.[2][5] Roughly 24 hours after attaining hurricane intensity, the storm abruptly turned east in response to the trough.[2] Having defied initial forecasts, Hurricane Elena drifted on its new course toward the coast of northwest Florida. Forecasters now called for the trough to direct the hurricane across the Florida Peninsula and into the western Atlantic. However, the relatively weak trough moved rapidly, and instead of fully engaging Elena, its axis passed over the storm's center. Further, post-storm analysis of water vapor imagery suggested that the hurricane split the trough into two distinct segments.[4]

Hurricane Elena early on September 1, shortly before attaining peak intensity and accelerating to the west




Member Since: September 27, 2007 Posts: 1 Comments: 22322
2491. Skyepony (Mod)
Quoting 2478. Waltanater:
It's not official. NHC is the one that makes it official!

NAVY has declared it.. they used the name.. If this died in the water before NHC had a chance to declare it at 11 then the name is already used & the next name wouldn't be Dorian..
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EARL

Advisory 1


Advisory 18
Member Since: October 6, 2007 Posts: 0 Comments: 6454
TD 4/TS Dorian looking nice & the fat lady hasn't sung on my blob yet, she is still alive and well and can be found roughly at 55W 31N.

Member Since: June 30, 2013 Posts: 12 Comments: 8774
Quoting 2466. washingtonian115:
One similarity is that they are very small storms. I'm still meh about Dorian's future.It's gonna have to prove it's self to me a lot.


It certain proved a lot in just 5 hours. IMO Atlantic is putting her hands on that switch and attempting to light up our basin.
Member Since: May 25, 2012 Posts: 0 Comments: 2043
2486. VR46L
Quoting 2473. Grothar:


Never happen.


I hope you are right , But I think its more of a possibility than the Euro Solution at the moment. if it has not Turned North before the Islands and is a storm there is no reason why a US landfall could not Happen .. Very strong High aint going to let it go north IMO
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Good Morning All,

I see there is a Storm out there and this "Blog" is moving as fast as the storm is..... LOL

Taco :o)
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Quoting 2473. Grothar:


Never happen.

never say never
Member Since: June 13, 2009 Posts: 2 Comments: 12712
Wind speeds are still increasing by the look of satellite imagery. Link
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Quoting 2478. Waltanater:
It's not official. NHC is the one that makes it official!


ATCF is the data the NHC runs into the model. If that's not official then I don't know what is.
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2480. KEEPEROFTHEGATE (Mod)
Quoting 2473. Grothar:


Never happen.
nope right across north of the islands west nor'west ward all the way
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Quoting 2471. Grothar:


The intensity models aren't very strong
Quoting 2473. Grothar:


Never happen.


CMC gonna get this one right too?

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Quoting 2468. CybrTeddy:


He's been named, up to 50mph per the ATCF.
It's not official. NHC is the one that makes it official!
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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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