LARRY #18 - DISCUSSION

[AussieMark]

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WTNT42 KNHC 060251
TCDAT2
TROPICAL DEPRESSION LARRY DISCUSSION NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 PM EDT SUN OCT 05 2003

SATELLITE AND SURFACE OBSERVATIONS INDICATE THAT LARRY HAS CONTINUED
TO MOVE INLAND OVER MEXICO AND HAS ALSO WEAKENED DOWN TO A TROPICAL
DEPRESSION. A SMALL BURST OF CONVECTION HAS DEVELOPED JUST SOUTH OF
THE LOW-LEVEL CENTER...WHILE A BAND OF DEEPER CONVECTION HAS
DEVELOPED 150-200 NMI EAST OF THE CENTER. THE OVERALL CIRCULATION
REMAINS WELL ORGANIZED DESPITE BEING INLAND.

THE INITIAL MOTION ESTIMATE IS 205/03. LARRY IS EXPECTED TO CONTINUE
MOVING SOUTH OR SOUTHWESTWARD FOR THE NEXT 24 HOURS AND WEAKEN...
AND EVENTUALLY DISSIPATE AS A TROPICAL CYCLONE OVER LAND. HOWEVER
...ALL OF THE NHC MODEL GUIDANCE NOW TAKES A WEAK SURFACE LOW AND A
BETTER LOOKING 850-500 MB VORTICITY CENTER ACROSS MEXICO AND INTO
THE GULF OF TEHUANTEPEC IN 36-38 HOURS. I WOULD IMAGINE THAT
INTERMITTENT CONVECTION WOULD CONTINUE TO DEVELOP NEAR THE CENTER
OF THE REMNANTS OF LARRY...AND KEEP THE CIRCULATION FROM COMPLETELY
SPINNING DOWN. AS SUCH...IT WOULD NOT BE OUT OF THE QUESTION FOR
SOME REGENERATION TO OCCUR...IF THE SYSTEM EMERGES OVER THE VERY
WARM WATERS OF EASTERN NORTH PACIFIC OCEAN.

THE GFDL MODEL WEAKENS LARRY OVER LAND DOWN TO 25 KT...THEN
RE-INTENSIFIES THE SYSTEM BACK TO A TROPICAL STORM IN 48 HOURS AND
MAKES IT A 95-KT HURRICANE BY 96 HOURS NEAR MANZANILLO. THE SHIPS
INTENSITY MODEL IS NOT AS ROBUST AS THE GFDL...BUT IT ALSO
REGENERATES LARRY BACK TO A TROPICAL STORM IN 48 HOURS BUT PEAKS AT
73 KT IN 96-120 HOURS UNDER LIGHT SHEAR CONDITIONS OF LESS THAN 5
KT. OF COURSE...ANY REGENERATION WILL DEPEND ON WHETHER OR NOT THE
REMANT CIRCULATION COMES BACK OVER WATER OF IF IT STAYS INLAND OVER
MEXICO.

FORECASTER STEWART

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/0300Z 17.9N 94.0W 30 KT
12HR VT 06/1200Z 17.3N 94.1W 25 KT...INLAND
24HR VT 07/0000Z 16.6N 94.3W 20 KT...DISSIPATING INLAND
36HR VT 07/1200Z...DISSIPATED INLAND