Two African waves worth mentioning

By: Dr. Jeff Masters , 3:51 PM GMT on July 18, 2009

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There are two African tropical waves worth mentioning today, though neither looks particularly threatening. A tropical wave near 12N 45W, about 1200 miles east of the Lesser Antilles Islands (97 L), is moving west at 15 - 20 mph. This wave is now surrounded by an area of very dry air from the Sahara Desert. The dry air has disrupted most of the wave's heavy thunderstorm activity, and will continue to make it difficult for this system to develop over the next 2 - 3 days. Wind shear is a modest 10 knots over the disturbance, and should remain in the moderate 10 - 15 knot range over the next 2 - 3 days. Thereafter, shear is expected to rise to 20 - 30 knots. This morning's QuikSCAT pass showed no evidence of a surface circulation, and only a modest wind shift associated with 97L. The National Hurricane Center is giving this system a low (less than 30% chance) of developing into a tropical depression in the next 48 hours.

A second tropical wave now approaching the northern Lesser Antilles Islands is under 30 knots of wind shear, and has little prospect of development due to the high shear. However, the wave will bring heavy rain to the islands over the next two days.

None of the computer models are forecasting tropical storm development over the next seven days, and I don't expect either of the two African waves mentioned today to develop over at least the next three days.


Figure 1. Current satellite image of African wave 97L, 1200 miles east of the Lesser Antilles Islands.

I'll have an update Sunday afternoon.
Jeff Masters

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This blog should be its own day-time soap opera..


Will it devlop? Find out next time... Exept you don't find out next time beacuse the next episode is called D-MIN..
Member Since: Posts: Comments:
2099. JRRP
Quoting BurnedAfterPosting:


not to get on your case

but why do you think the circle will be removed?

just to make the difference
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Quoting Weather456:


Who would vote for d? lol


JRRP did just for laughs :P
Member Since: July 7, 2008 Posts: 2 Comments: 3237
What would keep 97L from rapid intensification? Sorry if thats a dumb question, im just curious..lol.
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Oooooo....97L is getting that "screaming eagle" look. Ana in the making?
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Quoting HurricaneSwirl:


ok we've had a, b, and c now.. d anyone? d?


Who would vote for d? lol
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2094. WAHA
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!

C
Definitely c
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!

orange orange orange 1oo%
Member Since: June 13, 2009 Posts: 2 Comments: 11951
Quoting GaleWeathers:
Anyone know what's up with South Florida NEXRAD? It's been down for a few days now. All three stations.


They are replacing the old radar with a new one
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Quoting JRRP:

D
B
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Quoting JRRP:

D


not to get on your case

but why do you think the circle will be removed?
Quoting extreme236:


I'm thinking B or C...I can't decide. Depends on how they want to approach it.


yeah theres no telling what the nhc will do lol.
They could keep the yellow, too.
Member Since: July 7, 2008 Posts: 2 Comments: 3237
97L looks better now than it did a few hours ago. This is very interesting. Could this be Ana?
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2087. JRRP
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!

D
:p
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Quoting IKE:


Based on the closeness to the islands...they better put some thought into the new TWO. It's only 500 miles +/-, from Barbados.


Yeah

I suspect our MET service might issue a ''flood watch/warning'' later today or tonight....
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I pessimistically vote A.
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Quoting HurricaneSwirl:


ok we've had a, b, and c now.. d anyone? d?


B
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2083. Drakoen
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


B
Member Since: Posts: Comments:
2060. BurnedAfterPosting

A) Yellow
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Quoting extreme236:
14:45 UTC Nasa image shows more symmetrical central convection.


Would this be the same as a CDO?
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Quoting WPBHurricane05:


c


ok we've had a, b, and c now.. d anyone? d?
Member Since: July 7, 2008 Posts: 2 Comments: 3237
Tropical wave in the EPAC showing some life as well:

Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


B
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


Orange
Member Since: Posts: Comments:
I'm more concerned with its troubling forward speed than any other inhibiting factor in the present.
Member Since: Posts: Comments:
2074. WxLogic
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


A
Member Since: August 14, 2008 Posts: 4 Comments: 4972
2073. IKE
12Z NAM
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B. Orange.
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Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


It will be A but I think it should be B...
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14:45 UTC Nasa image shows more symmetrical central convection.
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


c
Member Since: July 31, 2006 Posts: 56 Comments: 8112


It's alive! IT'S ALIVE!
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


I love this. I will go with A
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Member Since: Posts: Comments:
I vote orange,but i really think it should be red.
Member Since: Posts: Comments:
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


B!!!
Lol we should do this every TWO update.
Member Since: July 7, 2008 Posts: 2 Comments: 3237
Quoting BurnedAfterPosting:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!


orange
Member Since: Posts: Comments:
Anyone know what's up with South Florida NEXRAD? It's been down for a few days now. All three stations.
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Well 93L never had much going on it its surface for much of its life.
Member Since: Posts: Comments:
LOL there is another poll question we can do

only answer once

Which color will the circle be at 2pm

A) Yellow
B) Orange
C) Red
D) Circle will be removed

VOTE NOW!!
2059. IKE
Quoting BurnedAfterPosting:


then again they were burned with doing that for 93L, they may stay conservative for the 2pm and see if the organizational trend continues throughout the day.


Based on the closeness to the islands...they better put some thought into the new TWO. It's only 500 miles +/-, from Barbados.
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I don't see much dry air anymore according to water vapor - it's already expanding its moisture field, now pulling moisture from the dissipating upper trough ahead of it in its path. This "shear" that's out in front, too imo, will not be as much of a factor at the sfc where it is still developing and finally it may serve to aid in venting as it crosses into the eCaribbean.
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Quoting BurnedAfterPosting:


then again they were burned with doing that for 93L, they may stay conservative for the 2pm and see if the organizational trend continues throughout the day.


Nah, they will probably mention it showing signs of organization and/or having become better organized. I see orange...perhaps red later tonight if the trend continues.
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Quoting wunderkidcayman:
good morning everyone I see we have invest 97l back on and forecasting to be a caribbean system can someone give me a proper update



hey, you can check out my blog to get up to speed
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Quoting IKE:


If it continues to look as good as it does, if not better...I say yes.



then again they were burned with doing that for 93L, they may stay conservative for the 2pm and see if the organizational trend continues throughout the day.


if that trough lifts out imo we'll have something real to track.
Member Since: July 7, 2008 Posts: 2 Comments: 3237
2052. IKE
Quoting BurnedAfterPosting:


you think we will see the NHC bump the chances up from yellow to orange?


If it continues to look as good as it does, if not better...I say yes.

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good morning everyone I see we have invest 97l back on and forecasting to be a caribbean system can someone give me a proper update
Member Since: June 13, 2009 Posts: 2 Comments: 11951
Quoting IKE:


What is unfavorable to him? Is he saying?
He says once it moves further west winds aloft are to fast.But every day they have been weakening.I think the thing is that twc copys everything the nhc says.
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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.