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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1050. surfmom
Quoting leftovers:
sometimes these systems either build themselves favorable areas or find little favorable spots where to wind themselves up.

I hear ya Left, ...guess what I'm looking for...LOL
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this is the real map...
What about the bulge at the equator that developed in 1998? There are now axial tilt issues and the land under the poles began to rise which is also speeding up the ice cap melting. Why is this apparently being ignored?
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1047. surfmom
Hummmm -- bit of activity stirring.....be interesting to see this tomorrow. till then
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Quoting hahaguy:


It's a fake.


He should of made it code red :P
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Quoting Becca36:
Thanks.:)


No problem, anytime. I will try my best to help you out, i'm not an expert, but I have been tracking storms for 10 years.
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1042. hahaguy
Quoting canesrule1:
i dont see that on the website (i dont see the third one by africa)


It's a fake.
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Quoting jasoniscoolman09:
i dont see that on the website (i dont see the third one by africa)
Quoting Funkadelic:


I do see it has gotten a LITTLE better looking on satelite..and seems to have grown in size a bit.. But D-MAX tonight will determine if ex97L has life in her


Exactly my point
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97L is trying to refire. Approaching warmer sst near 50w.
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hey the image looks pretty legit when you zoom in... lol

nice try tho
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1036. Becca36
Thanks.:)
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Quoting Becca36:
Hi. Ive been a lurker for over a year and have always been fascinated by the weather. I've aquired quite an education on here through reading posts and following links.Just wanted to say hi. I'll mostly lurk but if I have a question no one else asks I'll ask but please be easy on me, I am only self educated about meteorology! :) Oh, nice to finally meet you all!


It's all good, we are all here to learn and help. :)
Nice to meet you to.
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Quoting Drakoen:
You can tell it has been edited lol.


yea I guess, not a very smart thing to do on this blog though
Good evening everyone, can someone please inform me with the current status, was out for a while because something big happened in the building next to ours.
1031. Drakoen
You can tell it has been edited lol.
Member Since: October 28, 2006 Posts: 57 Comments: 29714
1030. Becca36
Hi. Ive been a lurker for over a year and have always been fascinated by the weather. I've aquired quite an education on here through reading posts and following links.Just wanted to say hi. I'll mostly lurk but if I have a question no one else asks I'll ask but please be easy on me, I am only self educated about meteorology! :) Oh, nice to finally meet you all!
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Quoting stormwatcherCI:
You are entitled to your opinion. I don't think you need to explain yourself to anyone.


I know but someone complained that I was over hyping the remnants of 97L, so I had to get that straightened out.
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Quoting jasoniscoolman09:


you should be banned for putting up a fake TWO map, there is no yellow circle by the CV Islands
Quoting reedzone:


I said on an earlier post that there is a LOW but fair chance for regeneration. I am seeing very small thin banding features on the wave, doesn't mean I'm calling it a storm just yet ;)
I also mentioned I am giving it 14 hours to regenerate, if it falls apart by Sunday morning, I won't be tracking it anymore. Conditions are better and a bit more moist. However, there is still some dry air left to contend with. So it's a wait and see deal, not over hyping.
You are entitled to your opinion. I don't think you need to explain yourself to anyone.
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1025. Drakoen
GFS shows shear lowering in the coming days and the overall mean shear lowering as we head into August.
Member Since: October 28, 2006 Posts: 57 Comments: 29714
Thanks Storm :)
G'night.
Member Since: August 2, 2006 Posts: 0 Comments: 1240
Quoting TampaFLUSA:

Dude you need to calm down no offense, but your over-hyping this storm on this blog I noticed.


I said on an earlier post that there is a LOW but fair chance for regeneration. I am seeing very small thin banding features on the wave, doesn't mean I'm calling it a storm just yet ;)
I also mentioned I am giving it 14 hours to regenerate, if it falls apart by Sunday morning, I won't be tracking it anymore. Conditions are better and a bit more moist. However, there is still some dry air left to contend with. So it's a wait and see deal, not over hyping.
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Quoting reedzone:


Evening StormW, great analysis! Both of these features need to be watched. Convection is starting to fire up on the remnants of 97L, a banding look.

Dude you need to calm down no offense, but your over-hyping this storm on this blog I noticed.
Member Since: June 21, 2007 Posts: 10 Comments: 1657
Quoting Drakoen:


At diurnal maximum then system has to hold it's convection for approximately 12 hours. During this 12 hours the system has to prove itself capable of generating and/or regenerating convection.
Thanks.
Member Since: October 9, 2008 Posts: 0 Comments: 8242
Quoting StormW:
Have a great evening. I'm out.

TROPICAL WEATHER "QUICKCAST" JULY 18, 2009 ISSUED 8:30 P.M. EDT


Evening StormW, great analysis! Both of these features need to be watched. Convection is starting to fire up on the remnants of 97L, a banding look.
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Seems like these two waves are going to have a hard time if any developing. So what made these "worth mentioning"?

Just curious...
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Quoting StormW:
Have a great evening. I'm out.

TROPICAL WEATHER "QUICKCAST" JULY 18, 2009 ISSUED 8:30 P.M. EDT

Makes sense, no hype.
Member Since: June 21, 2007 Posts: 10 Comments: 1657
Called my sister in St. Thomas. She lives up on the side of a mountain. She had no idea anything was coming. But happy with the news because they are almost out of water.. During our conversation the line got really bad and then just cut off..

Thanks for GeoffreyWPB for posting that radar.
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Quoting Drakoen:
People keep spelling my username name wrong. Just "Drak" is fine (LOL!)

Hey Adrian,

Yea, nothing imminent out there.


My bad, just fixed it.
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1014. Drakoen
People keep spelling my username name wrong. Just "Drak" is fine (LOL!)

Hey Adrian,

Yea, nothing imminent out there.
Member Since: October 28, 2006 Posts: 57 Comments: 29714

AOI

AOI

AOI
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Hey Drakoen,

All is quiet brother,the wave bringing squally weather to the northern islands is all interaction with the upper trof in the area.Just before heading out to fridays with wifey i was looking at some visible imagery of the caribbean and i was picking up the mid-level circulation racing ahead of the wave.Looks like that squally weather might make its way into southern florida come mid week.
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1011. Drakoen
Quoting stormwatcherCI:
When do systems or invests normally get better organized ?


At diurnal maximum then system has to hold it's convection for approximately 12 hours. During this 12 hours the system has to prove itself capable of generating and/or regenerating convection.
Member Since: October 28, 2006 Posts: 57 Comments: 29714
Quoting sporteguy03:


Reedzone Invest eh?


If it continues to organize tonight, possibly re-tagged by Sunday afternoon. A low but fair chance of that happening.
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Quoting Drakoen:
Quoting PcolaJess:
am usually just a lurker but what is DMAX?

When the difference between the ocean temperature and the atmosphere is at it's greatest occurring before sunrise.
When do systems or invests normally get better organized ?
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1008. Middy83
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oh cool thanks drak and glad to see you are back
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1006. Drakoen
Quoting PcolaJess:
am usually just a lurker but what is DMAX?

When the difference between the ocean temperature and the atmosphere is at it's greatest occurring before sunrise.
Member Since: October 28, 2006 Posts: 57 Comments: 29714
Quoting PcolaJess:
am usually just a lurker but what is DMAX?


Thanks was gonna ask the same question..
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1004. Patrap
GOES-12 Atmospheric Imagery

These images are primarily for use in tropical storm monitoring. There are several areas to choose from providing a large-scale view of the Atlantic, down to the Gulf of Mexico. During hurricane season, the hurricanes page provides a variety of GOES atmospheric products to help monitor the active storms.
Member Since: July 3, 2005 Posts: 414 Comments: 125476
Quoting PSLHokie:
wow, the 30-50 knots of shear really did in the Caribbean blobb!!!!


and you are surprised?
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1002. Patrap


Atlantic Ocean View (Updated ~3 hours)
Member Since: July 3, 2005 Posts: 414 Comments: 125476
am usually just a lurker but what is DMAX?
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Quoting reedzone:
The remnants of 97L are actually making a comeback

Photobucket

Banding features are "trying" to form to the north. DMAX is currently doing this storm good, it's also now entered a much better environment. I will be watching this closely throught the night.


Reedzone Invest eh?
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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.