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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2150. beell
B
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Quoting weathersp:


Herbert Box....

*Ducks anc covers and waits for the blog to explode*


from the looks of this, it may go through BOTH hebert boxes *also ducks*
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Notice the convective band ahead of 97L is not being sheared. That is a trick I learn back in 04. That signals potential for continued development of this system.
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2147. WxLogic
I'm pretty sure NHC will wait until 8PM or 2AM to give it some time through DMIN to see if it keeps up and/or builds more TSTM(s) around it, as well as get other sources to confirm better organization has occurred. At least that's what I would do... hehe.
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Looks to have some outflow.
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The hurricane hunters might want to investigate this invest in the upcomming days.
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Quoting IKE:
Looks to me like the center may go just north of Barbados...


Ike, I think you're right. The nudge from coriolis may be a positive sign that it's getting its act together and a low-level coc may be forming.
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2143. WAHA
Quoting WAHA:

Almost?
No, i am sure you didn't finish because all you picked was b.
img
src="http://www.ssd.noaa.gov/goes/flt/t1/wv.jpg" alt="" />
But I think it is C.

oops no image
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Quoting HurricaneSwirl:


ooohh your in trouble now. from now on, if a major strikes south florida, its all YOUR fault.


Herbert Box....

*Ducks and covers and waits for the blog to explode*
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Quoting Drakoen:


Upload pic into profile


thx, apparently i uploaded it in the wrong place. >.> never was good with common sense :D



wow on the loop ike posted, look at the first frame, and then look at the last. if it continues this... just wow
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2139. IKE
Quoting CaneWarning:
IKE, that thing is starting to look nice.


Agree.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting STORMMASTERG:
The prize of a near ready storm.


Cool, as long as it's a very weak one.
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2137. Drakoen
Quoting stormwatcherCI:
Latest wv image looks like trouble in the making. Expert opinions please .


There are no PhD's in here lol
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2136. WAHA
Quoting LiveFromTheCarolinas:


I will go with B since I have noticed that B is often the correct answer on multiple choice tests. That's how I got through highschool (almost).

Almost?
No, i am sure you didn't finish because all you picked was b.
img
src="http://www.ssd.noaa.gov/goes/flt/t1/wv.jpg" alt="" />
But I think it is C.
Member Since: Posts: Comments:
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2134. IKE
Looks to me like the center may go just north of Barbados...
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Good morning
Member Since: May 16, 2009 Posts: 1 Comments: 1231
I vote b we could see a TD by monday
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IKE, that thing is starting to look nice.
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2130. Drakoen
I should take into consideration what forecaster is on duty today lol.
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Latest wv image looks like trouble in the making. Expert opinions please .
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Quoting WPBHurricane05:
What prize do I get when I win (I voted code red)?
The prize of a near ready storm.
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2127. IKE
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting LiveFromTheCarolinas:


I will go with B since I have noticed that B is often the correct answer on multiple choice tests. That's how I got through highschool (almost).


LMAO... My choice was always C... explains why I graduated with a C average. Should have gone with B.
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I choose A but I may be wrong but thats the fun

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I vote "B".
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2123. JRRP
Quoting Drakoen:


It's: "He did it for the lolz"

explain me
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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!!


I will go with B since I have noticed that B is often the correct answer on multiple choice tests. That's how I got through highschool (almost).
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What prize do I get when I win (I voted code red)?
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Quoting JRRP:

A
A=unreal
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2119. Drakoen
Quoting HurricaneSwirl:


my bad then lolz

btw how do i upload an avatar.. i uploaded a pic and it said upload successful, now what? XD


Upload pic into profile
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Thanks drake,456 and moonlight.
I was just curious about that because some storms do and some dont.
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Quoting BurnedAfterPosting:
Not sure why I am being reminded of Charley lol


ooohh your in trouble now. from now on, if a major strikes south florida, its all YOUR fault.
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Quoting HurricaneSwirl:


my bad then lolz

btw how do i upload an avatar.. i uploaded a pic and it said upload successful, now what? XD
Now you wait for approval from admin
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2115. WAHA
Quoting stormwatcherCI:
Why are you so angry ? Take off your cap locks and stop shouting. We can all hear fine. Thank you.

i couldn't've said it better myself.

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Quoting Drakoen:


It's: "He did it for the lolz"


my bad then lolz

btw how do i upload an avatar.. i uploaded a pic and it said upload successful, now what? XD
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2112. JRRP
Quoting BurnedAfterPosting:


ah ok lol, would you like to recast your vote?

A
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Quoting alaina1085:
What would keep 97L from rapid intensification? Sorry if thats a dumb question, im just curious..lol.


Its forward speed.
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2110. Drakoen
Quoting stormwatcherCI:
Maybe he Why are you so angry ? Take off your cap locks and stop shouting. We can all hear fine. Thank you.


lol
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Not sure why I am being reminded of Charley lol
2108. sngalla
orange
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Quoting BurnedAfterPosting:


not to get on your case

but why do you think the circle will be removed?
Maybe he
Quoting jasoniscoolman09:
I NEVER WATCH THE TWC.
Why are you so angry ? Take off your cap locks and stop shouting. We can all hear fine. Thank you.
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Quoting PensacolaDoug:
Oooooo....97L is getting that "screaming eagle" look. Ana in the making?


The "screaming eagle" is only a tropical wave being heavily sheared. 97L does not have a screaming eagle look. Our wave yesterday in the Antilles had a "screaming eagle" look, but not 97L
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2105. Drakoen
Quoting HurricaneSwirl:


JRRP did just for laughs :P


It's: "He did it for the lolz"
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Quoting alaina1085:
What would keep 97L from rapid intensification? Sorry if thats a dumb question, im just curious..lol.


If it ends up in the wrong position, shear

As the disturbance enters the Caribbean, shear depends mainly on an upper ridge building over the area and the invest’s motion. If the ridge should not build far enough north, the system could be affect by northerly shear in the Southeast Caribbean and hinder development of the feature. However, if the system was to remain on its westerly path it should avoid much of the higher shear to the north regardless of how long it takes the ridge to build and the TUTT to move out. Most of the global models are in favour of a fast building ridge. If the storm continues to persist through the day, I suspect a re-designation of 97L.
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Quoting HurricaneSwirl:


JRRP did just for laughs :P


sarcasm?

LOL...
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2102. Drakoen
Quoting alaina1085:
What would keep 97L from rapid intensification? Sorry if thats a dumb question, im just curious..lol.



Itself and marginal shear.
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Quoting JRRP:

just to make the difference
Quoting JRRP:

just to make the difference


ah ok lol, would you like to recast your vote?
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..
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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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