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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Quoting Tazmanian:
i do say this is geting annyoing



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i get that sometimes and yes its annyoing
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77. Tazmanian 4:26 PM GMT on July 18, 2009
i do say this is geting annyoing
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No kidding I had that a lot yesterday and even when I update my blog, it tells me blog does not exist..to create blog click here.
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Quoting Tazmanian:
i do say this is geting annyoing



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I get it too almost every time I refresh.
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Quoting KEEPEROFTHEGATE:


cloud tops have warmed slightly and convection has commence waning phase

are we in d-min
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the wave at 60W is blowing up due to wind shear and nothing else


Central Atlantic - Water Vapor Loop
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92. WAHA

RGB on 97.
Forget 97L for now maybe days in the future but not now, the unnamed wave looks a little better
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Quoting Patrap:
with 97L's quick movement is there a possibility 97L might crash with the blob over the U.S.V.I.
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cloud tops have warmed slightly and convection has commence waning phase
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88. 7544
second wave ? it called wave one the one thats blown up before 97l
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Quoting HurricaneSwirl:


The situation now. 97L is *almost* into a more moist environment. but then the shear will be the problem. shear could die down by the time it gets there though.

agreed
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86. IKE
Quoting willdunc79:
LOL Ike that would serve me right. MHO being both waves are going to go poof and then the model aims it right at me in NC.


LOL...sorry.
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Quoting weatherwatcher12:

Ok. I will keep an eye on 97L
yeah
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83. IKE
Quoting alaina1085:
Ike is anything supposed to form in the Gulf? I remember someone saying the models hinted at a development from that cold front or something of the sort.


Doesn't look like it now.

Just keep an eye on the 2 waves...something may make it into the GOM in a week.
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Quoting Tazmanian:
i do say this is geting annyoing



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agreed
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Is the 2nd wave moving?
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LOL Ike that would serve me right. MHO being both waves are going to go poof and then the model aims it right at me in NC.
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Quoting HurricaneSwirl:


The situation now. 97L is *almost* into a more moist environment. but then the shear will be the problem. shear could die down by the time it gets there though.
agreed
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Ike is anything supposed to form in the Gulf? I remember someone saying the models hinted at a development from that cold front or something of the sort.
Member Since: August 2, 2006 Posts: 0 Comments: 1240
Quoting canesrule1:
I would say its more of a hit or miss, even though its been around for more than 24 hours its a blob it comes and goes just think of this as a wall for 97L, this blob is moistening the path for 97L in other words.

Ok. I will keep an eye on 97L
Member Since: May 16, 2009 Posts: 1 Comments: 1231
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Quoting Tazmanian:
this 2nd wave has a better ch then 97L this 2nd wave is olny





the 2nd wave is olny in 30kt of wind shear wish is not that bad how evere has the wave move WNW it will go in too lower wind shear i think we sould turn are eyes on too this wave then 97L this 2nd wave is closer too home then 97L is and stan a better ch


Link
agreed this should also be watched as a threat to SE-FL, imo.
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73. IKE
Quoting willdunc79:
Ike if either wave SHOULD make a comeback then I can gladly say I'm wrong and accept my crow(dinner). It just seems like everyone who matters(which doesn't include post #35)is actually in agreement saying not to expect anything out of either wave and the more it's said and the more the odds (like high shear which is around the wave @60W) are against the waves more & more people are pushing extra hard it seems to find lil' thigs to be able to say"oh look I expect developement" but everyone has their opinion which I respect. It just so happens that my little humble opinion (MLHO) is that both waves will gradually go on away.


You may be right. Here's what Dr. Masters said...However, the wave will bring heavy rain to the islands over the next two days. ......

Whether it's ever an invest...a name or nothing...heavy rain over Haiti and DR can be life threatening/poof to humans.
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97L is surrounded on the left by Dry Air and ingesting it.
Bad way to survive..

Wah--wahhhhhhhhhhh

AL97 Floater - Water Vapor Loop
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The situation now. 97L is *almost* into a more moist environment. but then the shear will be the problem. shear could die down by the time it gets there though.
Member Since: July 7, 2008 Posts: 2 Comments: 3237
Quoting weatherwatcher12:

Should the more western islands watch this
I would say its more of a hit or miss, even though its been around for more than 24 hours its a blob it comes and goes just think of this as a wall for 97L, this blob is moistening the path for 97L in other words.
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69. IKE
Quoting Funkadelic:


True, but it he doesnt seem to impressed right now. Whats your thoughts on 97L running into all that moisture tonight during D-max?


Not sure what's going to happen w/97L...it may come back or die. Odds are it won't die.


12Z GFS aims the wave near the islands up the east coast of the US in 5-6 days(Carolina's....press). GFS has a right bias at times. I doubt this wave simply fades away.


Probably both waves are worth watching.
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Quoting Stormchaser2007:
Nothing.


look to the left side of the image imo
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Quoting centex:
97L is trying to stick a straw through the dry air and tap into the moisture in northern Lesser Antilles.
lol, true
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Quoting willdunc79:
so in short:

POOF

To both the tropical wave and to 97L.

Well I'm off to go do other things but will be back in the next invest/strong tropical wave that actually looks promising.
don't be fooled mother nature can be a little tricky
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Ike if either wave SHOULD make a comeback then I can gladly say I'm wrong and accept my crow(dinner). It just seems like everyone who matters(which doesn't include post #35)is actually in agreement saying not to expect anything out of either wave and the more it's said and the more the odds (like high shear which is around the wave @60W) are against the waves more & more people are pushing extra hard it seems to find lil' thigs to be able to say"oh look I expect developement" but everyone has their opinion which I respect. It just so happens that my little humble opinion (MLHO) is that both waves will gradually go on away.
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Quoting IKE:
Dr. Masters,

Your blog is kicking me out when I hit refresh. Not every time...maybe a third of the time. It's been going on for about 2 weeks now. I have to click a couple of links to get back in.
it me also be all the people blogging, its a lot of people on right now.
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Quoting canesrule1:
I think we should watch the wave around the U.S.V.I because not only is the convection there but its closer to not only the U.S but also Haiti, you all should watch this trust me, anyways u can say its persistent because its been around for over 24 hours.

Should the more western islands watch this
Member Since: May 16, 2009 Posts: 1 Comments: 1231
Quoting canesrule1:
me too

me to
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Quoting IKE:


He didn't write them off. He said..."I don't expect either of the two African waves mentioned today to develop over at least the next three days."......

He didn't say anything about the 4th day on...


True, but it he doesnt seem to impressed right now. Whats your thoughts on 97L running into all that moisture tonight during D-max?
Member Since: May 18, 2009 Posts: 0 Comments: 474
97L is trying to stick a straw through the dry air and tap into the moisture in northern Lesser Antilles.
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Quoting IKE:
Dr. Masters,

Your blog is kicking me out when I hit refresh. Not every time...maybe a third of the time. It's been going on for about 2 weeks now. I have to click a couple of links to get back in.
me too
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stormjunkie you what you think by the way check your email
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Some server issues,.do not change your password during this event,..
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Quoting RufusBaker:
Oh here ya are Ruuuuuufus Baker!! The mighty two tone talk the two tone talk!!! yeeeeeeeeee hawwwwwwwwwwwww
and you will be replaced with empty space
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Quoting IKE:
Dr. Masters,

Your blog is kicking me out when I hit refresh. Not every time...maybe a third of the time. It's been going on for about 2 weeks now. I have to click a couple of links to get back in.


me too, about half the time it'll say something like "Dr. Masters does not have any blog entries" blah blah blah. I'll have to refresh again.
Member Since: July 7, 2008 Posts: 2 Comments: 3237
64km radar from Hong Kong Observatory at midnight HKT (noon EDT)

Typhoon Molave
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52. 7544
hmm new gfs run is wacky now
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I think we should watch the wave around the U.S.V.I because not only is the convection there but its closer to not only the U.S but also Haiti, you all should watch this trust me, anyways u can say its persistent because its been around for over 24 hours.
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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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