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New African wave

By: Dr. Jeff Masters, 1:18 AM GMT on August 21, 2006

Well, our quiet days in the Atlantic didn't last very long, as it's time to talk about a new threat area. A very vigorous tropical wave has moved off the coast of Africa today, and has the potential to develop into a tropical depression later this week. The waters under the wave are 27-28 C, which is .5-1.5 degrees C above the 26.5 C threshold for tropical cyclone formation--not great, but good enough. Wind shear is a modest 10 knots. There is a large area of dry air and Saharan dust to the wave's north, and this will likely be the major inhibiting factor for this wave.

Both the GFS and NOGAPS models develop the wave into a tropical storm; the UKMET does not. The GFS predicts the storm will pass well north of the Lesser Antilles Islands.


Figure 1. Preliminary model tracks for the new African tropical wave.

I'll have much more on this system Monday, plus a look at the rest of the tropics.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Mornin Oreo....cheery, as usual!

Always ready to run.....SO far away! :)
thank you Mah, weather,hobe, and Taz. mmm if it's 25 knots why is it not TD #4 yet? to get mph don't you multiply # (25 kts.) by 1.5?
505. MahFL
multiply by 1.15. Also a closed low is needed.
hey this look like a TS now what you all think
Ioke Intensity at 9:00amEDT

Curved Band Pattern/Cloud Pattern
> 0.4 Spiral - DT 1.5

Shear Pattern
None - 0.00

CDO
-CDO Central Feature

-1 degrees latitude- DT 2

-CDO Banding Features

Has Improved - DT 1

Further Considerations (environmental factors)
Eye, now evident on the Stortwave Imagery

Ioke T Number is 1.5+2+1=4.5

4.5 is 88.5mph, 979mbar MCP.
508. MahFL
The NHC are proberbly drinking coffee and eating dounuts.....or is that the cops ? lol.
I doubt they would call this a TS yet, its only happened a few times that i can remember- that they skipped TD and went to TS. The NHC just knows that even if a wave coming off the coast looks good, it most likely will not hold together. No waves yet have looked very impressive after being off the African coast for more than 2 days this year. Maybe this wave will change all that though.
...THE ITCZ...
ITCZ AXIS IS CENTERED ALONG 14N16W 7N25W 9N34W 8N40W 12N55W
10N62W ACROSS THE N PORTION OF SOUTH AMERICA AND PANAMA INTO THE
E PACIFIC REGION. A TROPICAL WAVE IS ALONG THE COAST OF AFRICA
WITH A BROAD MID LEVEL ROTATION OBSERVED ON INFRARED SATELLITE
IMAGERY BUT WAS NOT ANALYZED AS SUCH DUE TO THE LACK OF
SUPPORTING SURFACE AND UPPER AIR DATA.

My guess is they won't do much with 96L until that void is filled. Latest quickscat missed the area.

Good morning everyone!
dropping in briefly before work (ugh!) i would rather hang with ya'll today! I see that 96L is progressing quite nicely.
..G Morning reeldrlaura...Port Sulphur getting T-storm right now....going to b rainy here looka Lika..
96L Estimated Intensity at 9:00pmEDT

Curved Band Pattern
Little/None - 0.00

Shear Pattern
None - 0.00

CDO
-CDO Central Feature

0.5 degrees latitude- DT 1.33

-CDO Banding Features

Not much -DT 0.12

Further Considerations (environmental factors)
The cyclone moving into the southwest quadrant of the Upper-Level Anticyclone.
The cyclone moving over warm SSTs.

96L T Number is 1.33+0.12=1.45

1.45 is 29.9mph, 1008mbar MCP/Strong Tropical Disturbance

96L is also a Standard Developer
new blog up
Hey Pat......rain sounds good.....
I'm off to make hay while the sun shines

FISH STORM is my mantra!!!!
517. HCW
Don't look if your in LA to AL


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