Disturbance 90L close to tropical depression strength; TD 2 may rise again
A strong tropical wave (90L), with a large circulation and a moderate amount of heavy thunderstorm activity, is a few hundred miles southwest of the Cape Verdes Islands, off the coast of Africa. This morning's QuikSCAT pass shows that 90L has a large circulation, but this circulation is not yet well-formed, as it is elongated along an east-west axis. Satellite imagery from the European METEOSAT satellite show that the heavy thunderstorms associated with 90L are gradually becoming better organized, with some spiral banding evident on the south side of the storm. Satellite intensity estimates from NOAA already put 90L at tropical depression strength with 30 mph winds, but the storm does not yet have a well enough formed circulation to be classified as a depression. Water vapor imagery shows that since 90L is forming several hundred miles south of the dry air of the Saharan Air Layer (SAL), the storm should not be affected by dry air and dust as much as Tropical Depression Two was. However, there is some dry air from the SAL being sucked into the circulation of 90L, and this is retarding its development.
Wind shear is moderate, about 10 - 15 knots, but is forecast to fall to the low range, 5 - 10 knots, later today. Shear is then forecast to remain low for the next five days. Sea Surface Temperatures are about 28°C, and will remain in the 27 - 28°C range the next five days. The combination of low wind shear and sufficiently warm SSTs should allow 90L to develop into a tropical depression by Saturday, and potentially reach hurricane strength by Wednesday. Most of our reliable models strengthen 90L into a hurricane by Wednesday, when the storm is expected to be near the northern Lesser Antilles Islands. One important outlier is the ECMWF model, which has 90L passing to the north of the islands, and eventually recurving out to sea east of Bermuda. The ECMWF was by far the most reliable model for forecasting hurricane tracks last year. However, all of our models are pretty unreliable going out 5 days in advance for systems that have yet to reach tropical depression strength. Once 90L becomes a tropical depression and develops a well-formed circulation, the models will have a better handle on forecasting where it will go.
Figure 1. The remnants of Tropical Depression Two (left side of image) and tropical wave 90L (right side of image).
Tropical Depression Two may come back
Tropical Depression Two died yesterday, but may rise again. Satellite loops of the remnants of the storm show that heavy thunderstorms are again attempting a comeback near the axis of what is now a tropical wave. However, dry air continues to interfere with the development of the thunderstorm activity, and moderately high wind shear of 15 - 20 knots is also inhibiting the process. Wind shear over the remnants of TD 2 is expected to remain in the moderate range, 10 - 20 knots, over the next four days. Sea Surface Temperatures (SSTs) are 27°C, but will warm to 28°C two days from now. There is plenty of dry, stable air from the Saharan Air Layer (SAL) to the north and west that will continue to cause the storm problems. The relatively cool SSTs and dry air mean that any re-development of the storm will be slow to occur. NHC has given the system a medium (30 - 50% chance) of becoming a tropical depression again by Sunday morning. Only one reliable model, the NOGAPS, is predicting regeneration of TD 2. The NOAA Hurricane Hunters are flying research missions into the remnants of TD 2 today and Saturday.
I'll have an update Saturday morning, or earlier, if significant developments occur.
Jeff Masters
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HWRF
Link
No. Look at the cone, its much larger than that.
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm
----- Current Analysis -----
Date : 15 AUG 2009 Time : 034500 UTC
Lat : 14:35:39 N Lon : 45:32:41 W
CI# /Pressure/ Vmax
3.4 / 995.2mb/ 53.0kt
Final T# Adj T# Raw T#
(3hr avg)
3.4 3.4 3.4
Latitude bias adjustment to MSLP : +0.0mb
Center Temp : -57.6C Cloud Region Temp : -44.8C
Scene Type : CURVED BAND with 0.71 ARC in LT GRAY
Positioning Method : FORECAST INTERPOLATION
Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : ATLANTIC
Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF
****************************************************
I was just getting ready to post the same thing
Just like the EPAC was with Felicia. Weird how tropics transition from one side to the other.
I can't say but it isn't out of the realm of possibility.
Yes, 90L will either absorb TD2 or follow it closely.
Just forecast to be a TS right?
Orca you don't understand facts ......
You wait 2 seconds! JK!
14/2345 UTC 15.2N 44.9W T1.5/1.5 02L
ts anyone ?
CI# /Pressure/ Vmax
3.4 / 995.2mb/ 53.0kt
good question
Nah! It will most likely do what they always do with the curve right before it hits S. Fla. It amazes me how they do that all the time. With S. Fla already being in the cone, we should be safe as we always seem to fade out of it.
lol
There's a blackout each night from around now until ~4AM.
if that is correct then TD2 is moving in south track
Link
Thats when recon goes in and tells everyone they are just doing a drop-sound when they are really seeding it.
I know...And everyone always falls for the hype too!!! LOL
2004 by 4 separate systems, 2008 4 times by one system.
Yeah I know!!!! And everyone always fall for the hype too! LOL!
latest as of 415 utc
2004 had Charley, Frances, Ivan and Jeanne. We got hit with Frances and Jeanne where I live. The year after that we had Wilma.
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