25 September 2002

Isidore still huge but weak, Kyle nearly a hurricane, Lili losing to shear.

Very little has changed with Isidore since he exited the Yucatan
Peninsula.  Without question, the most notable feature of the storm is
its size.  It has lost all central convection, but the low and mid-level
swirl (including an area of tropical-storm-force winds 800km in
diameter) is now perhaps 2000km across in the E-W direction and 3000km
across in the N-S direction.  The outflow, assisted by a mid-latitude
trough to the north and the ITCZ to the south extends from just west of
Costa Rica and up to central NY.  See
for an impressive basin-wide VIS shot.  At 15Z TS Isidore was located at
26.0N 90.2W (430km south of New Orleans) and tracking N at 11kts. 
Intensity is 50kts and 990mb, indicating that the Low is filling
(pressure is rising).  However, a Tropical Storm Warning is in effect
from approximately Galveston, TX to Apalachicola, FL and a Hurricane
Watch is in effect for all of the LA and MS coasts.  

Landall is expected to be during the early morning hours on Thursday in
eastern LA.  The forecast is for gradual strengthening before landfall
(perhaps not to a hurricane though), then to track over the southeast
U.S. and up to the northeast, passing over TN, PA, and ME as landmarks
along the way.  This journey will be part of his merging with a
mid-latitude trough... forcing him to become extratropical.  By the time
the remnants are over Pennsylvania, New York, and New England on Friday,
there could potentially be a very big rain event, not to mention wind. 
The convective patterns and wind structure already indicate that Isidore
may be losing tropical characteristics... however, this does certainty
not mean he is no longer a threat.

TS Lili has been having problems dealing with vertical shear (only 10kts
SW-erly, but the convection is displaced from the low-level center
nevertheless).  The storm is poorly organized and even aircraft flying
through the system had difficulty finding the center.  But conditions
are expected to improve (depending on track), allowing her to once again
approach hurricane strength during the weekend.  The 15Z position was
14.1N 69.3W and movement was WNW at 10kts.  She is a weak TS with 40kt
sustained winds and a 1008mb MSLP.  A Tropical Storm Watch is in effect
for most of the southern coast of Hispaniola and I suspect that
southeast Cuba will also soon issue a watch.  The official forecast is
an outlyer in terms of track... NHC is going north of most of the model
tracks, which agree on taking her between Jamaica and Cuba and
eventually into the Gulf.  That version of the track forecast would be
less favorable for her development, but as I said, the models are in
pretty good agreement on that, so we'll see.

TS Kyle is just now moving over 28C+ SSTs, and the convective pattern
indicates that he's taking advantage of the increased fuel source. 
Since this morning, an eyewall has formed; for the first time,
convection has wrapped all the way around the center.  As of 15Z, Kyle
was located at 29.2N 54.8W and heading WSW at 7kts.  Intensity is 60kts
and 990mb, very much on course to maintain the eye and reach hurricane
status later today... the third of the season.  The forecast is for
continued strengthening in the low shear and warming SST environment,
then weakening as a trough approaches and shears him apart (tough world
out there!).

The tropical wave I'd been mentioning the past couple days in the
central Atlantic has dissipated.

Please visit my tropical Atlantic headquarters.

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