[Tropical] Tropical Cyclone Discussion

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WTNT41 KNHC 180915
TCDAT1
TROPICAL STORM FAY DISCUSSION NUMBER  11
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL062008
500 AM EDT MON AUG 18 2008

THE AIR FORCE RECONNAISSANCE AIRCRAFT FIXED THE CENTER OF FAY OVER
CENTRAL CUBA TO THE SOUTHWEST OF THE ROTATION ALOFT APPARENT IN
RADAR IMAGERY.  WITH THIS FIX...THE INITIAL MOTION IS NOW 335/10.
ASCAT DATA SOUTH OF CUBA PRIOR TO LANDFALL SHOWED THE SURFACE
CENTER BECOMING ELONGATED...LIKELY IN RESPONSE TO THE CONVECTIVE
ASYMMETRY...AND SOME ADDITIONAL DISTORTION OF THE SURFACE
CIRCULATION IS LIKELY DURING THE PASSAGE OF THE CENTER OVER CUBA.
ALL TRACK GUIDANCE SUGGESTS THAT FAY WILL MAINTAIN A
NORTH-NORTHWESTWARD HEADING FOR ANOTHER 24 HOURS UNTIL IT REACHES
THE SUBTROPICAL RIDGE AXIS.  THE OFFICIAL FORECAST IS NEAR THE
RIGHT-HAND SIDE OF THE GUIDANCE ENVELOPE EARLY ON...BUT SOME
ADDITIONAL RIGHTWARD ADJUSTMENTS MAY BE NECESSARY IF THE CURRENT
CONVECTIVE STRUCTURE PERSISTS AND THE CYCLONE REMAINS VERTICALLY
CONNECTED.  THERE ARE LARGE DIFFERENCES IN THE TRACK GUIDANCE LATE
IN THE FORECAST PERIOD AND THE RUN TO RUN CONSISTENCY OF THE
GUIDANCE HAS BEEN VERY POOR.  GIVEN THAT...ONLY A SLIGHT EASTWARD
SHIFT HAS BEEN MADE LATER IN THE FORECAST PERIOD.

THE INITIAL INTENSITY REMAINS 45 KT...WITH THESE WINDS OCCURRING
JUST OFF THE NORTH COAST OF CUBA.  AN UPPER-LEVEL
LOW OVER THE EXTREME NORTHWESTERN CARIBBEAN SEA IS IMPEDING THE
OUTFLOW OVER THE WESTERN PORTION OF THE TROPICAL CYCLONE...AND SOME
WESTERLY SHEAR IS EXPECTED TO CONTINUE FOR THE NEXT DAY OR TWO.
GIVEN THIS PATTERN...RAPID STRENGTHENING IS NOT EXPECTED...BUT THE
SHEAR IS NOT EXPECTED TO BE STRONG ENOUGH TO PREVENT FAY FROM
REACHING HURRICANE STRENGTH BEFORE IT REACHES THE FLORIDA
PENINSULA.  THE OFFICIAL FORECAST IS CLOSE TO THE GFDL AND SHIPS
GUIDANCE.


FORECAST POSITIONS AND MAX WINDS

INITIAL      18/0900Z 22.5N  80.9W    45 KT...INLAND
 12HR VT     18/1800Z 23.5N  81.5W    45 KT
 24HR VT     19/0600Z 25.1N  82.0W    55 KT
 36HR VT     19/1800Z 26.6N  82.3W    65 KT
 48HR VT     20/0600Z 28.2N  82.2W    60 KT...INLAND
 72HR VT     21/0600Z 31.1N  82.0W    45 KT...INLAND
 96HR VT     22/0600Z 33.0N  82.0W    25 KT...INLAND
120HR VT     23/0600Z 35.5N  82.5W    20 KT...REMNANT LOW

$$
FORECASTER FRANKLIN



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