22 September 2002

Isidore nearly a CAT4 hurricane, Kyle turning tropical, TD13 forms and heading for Lesser Antilles.

Isidore has been maintaining constant intensity recently, but did
undergo rapid intensification yesterday afternoon (18mb drop between 09Z
and 21Z) as anticipated.  The track since entering the Gulf has been
following the northern coast of the Yucatan Peninsula VERY closely,
which is undoubtedly limiting him from becoming even stronger.  At 18Z
today, Isidore was at 21.7N 88.9W and heading WSW at 7kts.  Winds have
reached 110kts (gusting to 135kts) and the MSLP is 934mb.  The eye has
grown a bit since yesterday, from 18km to 37km.  A Hurricane Warning is
in effect for all of the western and northern Yucatan Peninsula.  He is
forecast to resume intensification once he pulls away from the Yucatan
coast, and with only 5kts needed to reach CAT4, that landmark should be
achieved later today.  The offical track forecast is a continued
westward drift, followed by a turn to the north, but the models are
still unable to agree on a track... anything from continuing westward
into central Mexico to as far east as the Lake Charles, LA area.  Chaos
reigns yet again.

STS Kyle continues to get better organized and is very close to being a
purely tropical system.  At 15Z today, he was located at 33.0N 49.9W
(1400km east of Bermuda) and stationary.  Max winds are 40kts and MSLP
is 1006mb.  The steering current is still very weak but he should drift
toward warmer SSTs and gradually intensify, perhaps reaching hurricane
strength by Wednesday.  There is no threat to land in the foreseeable
future.

At 21Z yesterday, the more westward tropical wave I mentioned in the
9/21 update was upgraded to TD13 based on satellite estimates.  It has
been getting better organized and should become the 12th named storm
(Lili) in the next day or so.  As we've seen several times this season,
the low-level center is mis-aligned with the convection, so one of three
things will happen: 1) convection will blow up over the center, 2) the
center will reform under the existing convection, or 3) the system will
degenerate back to a tropical wave.  My hunch is option (1) and the
Depression will strengthen as it heads west through fairly low shear and
amply warm SSTs (next name is Lili, FYI).  Interestingly, if they can
all cooperate, by late Wednesday there could be three hurricanes in the
Atlantic: Isidore, Kyle, Lili.  As of 15Z today, TD13 was located at
12.0N 52.0W (about 850km east of southern Lesser Antilles) and tracking
W at 20kts.  Intensity is 30kts and 1007mb.  Microwave imagery shows
some band-ish features, but it is not well organized.  The track
forecast is to pass through the central Lesser Antilles on Monday night
and Hispaniola Wednesday night.

The more eastward tropical wave I mentioned in yesterday's update has
made very little progress except in location.  It has a 1011mb Low
associated with it and is moving west at 12kts.  It's presently at about
12N 33W.  Assuming TD13 becomes TS Lili, the next number/name on deck is
14/Marco.


Please visit my tropical Atlantic headquarters.

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