LARRY #5 - DISCUSSION

[AussieMark]

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WTNT42 KNHC 022055
TCDAT2
TROPICAL STORM LARRY DISCUSSION NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 PM EDT THU OCT 02 2003

VISIBLE SATELLITE IMAGERY AND REPORTS FROM AN AIR FORCE RESERVE
HURRICANE HUNTER AIRCRAFT INDICATE THAT THEW LOW-LEVEL CIRCULATION
OF LARRY HAS BECOME BETTER DEFINED DURING THE DAY. THE AIRCRAFT
MEASURED A CENTRAL PRESSURE OF 995 MB...WITH MAXIMUM 1500-FT WINDS
OF 66 KT IN THE SOUTHWEST QUADRANT. BASED ON THIS...THE INITIAL
INTENSITY IS INCREASED TO 50 KT. LARRY IS STRONGER THAN ITS
SATELLITE SIGNATURE...AS SATELLITE INTENSITY ESTIMATES ARE ONLY 35
KT.

LARRY HAS DRIFTED ERRATICALLY SOUTHWARD SINCE YESTERDAY. HOW MUCH
OF THIS IS ACTUAL MOTION AND HOW MUCH IS REFORMATION IS NOT
CERTAIN. THE STORM REMAINS TRAPPED IN WEAK STEERING CURRENTS
BETWEEN TWO HIGH PRESSURE RIDGES...SO ANY MOTION WILL BE SLOW.
GUIDANCE HAS COME INTO SOMEWHAT BETTER AGREEMENT ON A SLOW MOTION
BETWEEN SOUTHEAST AND SOUTHWEST...SO THE FORECAST TRACK PHILOSOPHY
WILL BE CHANGED TO THAT OF A SLOW SOUTHWARD TO SOUTH-SOUTHWESTWARD
DRIFT THROUGH THE FORECAST PERIOD. IT SHOULD BE NOTED THAT WITH
THIS SLOW MOTION...THE POTENTIAL EXISTS FOR JUMPS IN THE POSITION
FROM ADVISORY TO ADVISORY OR AIRCRAFT FIX TO AIRCRAFT FIX.

THE CONVECTION ASSOCIATED WITH LARRY IS STILL POORLY ORGANIZED...AND
THERE IS SOME EVIDENCE OF WESTERLY VERTICAL SHEAR. THIS
COMBINATION SHOULD SLOW THE DEVELOPMENT...AND THUS THE INTENSITY
FORECAST CALLS FOR ONLY GRADUAL STRENGTHENING. IT IS UNCERTAIN HOW
THE STORM MAY INTERACT WITH THE MEXICAN COAST IN 24-48 HR...AND
THUS THE INTENSITY FORECAST DOES NOT CURRENTLY CALL FOR LARRY TO
BECOME A HURRICANE. HOWEVER...THE GFDL FORECASTS LARRY TO BECOME A
HURRICANE AND THE POSSIBILITY CANNOT BE RULED OUT.

WIND RADII HAVE BEEN REVISED BASED ON REPORTS FROM THE HURRICANE
HUNTER. IN THE SOUTHWEST QUADRANT...THE AIRCRAFT REPORTED 1500-FT
WINDS OF 60 KT WITHIN 30 NM OF THE COAST...WHICH DECREASED
DRASTICALLY TO 10-20 KT AT THE COAST.

FORECASTER BEVEN


FORECAST POSITIONS AND MAX WINDS

INITIAL 02/2100Z 20.4N 93.6W 50 KT
12HR VT 03/0600Z 20.1N 93.6W 50 KT
24HR VT 03/1800Z 19.8N 93.7W 55 KT
36HR VT 04/0600Z 19.5N 93.8W 60 KT
48HR VT 04/1800Z 19.2N 93.9W 60 KT
72HR VT 05/1800Z 18.5N 94.0W 60 KT
96HR VT 06/1800Z 17.5N 94.5W 40 KT
120HR VT 07/1800Z 16.5N 95.5W 20 KT...INLAND DISSIPATING