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FORECASTS IMAGERY ABOUT TPC RECONNAISSANCE

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HURRICANE BRET DISCUSSION NUMBER  14
NATIONAL WEATHER SERVICE MIAMI FL
11 PM EDT SAT AUG 21 1999
 
TWO IMPORTANT EVENTS HAVE OCCURRED TONIGHT. FIRST...BRET HAS RAPIDLY
INTENSIFIED TO A CATEGORY 4 HURRICANE ON THE SAFFIR-SIMPSON SCALE
AND THIS IS BASED ON WINDS FROM GPS DROPSONDES RELEASED IN THE
EYEWALL BY THE NOAA RECONNAISSANCE PLANE. WINDS TO 135 KNOTS WERE
MEASURED BY THE SONDES AT 60 METERS ELEVATION. THIS CORRESPONDS TO A
SURFACE WIND OF 115 KNOTS. WINDS OF 149 KNOTS WERE MEASURED AT 888
MB.
 
SECOND...BRET HAS CONTINUE TO MOVE NORTHWARD AND FASTER...ABOUT 9 TO
12 KNOTS. THIS INCREASES THE RISK FOR RESIDENTS ALONG THE TEXAS
COAST.  WATCHES AND WARNINGS HAVE BEEN ADJUSTED ACCORDINGLY.
 
A MIDDLE-LEVEL RIDGE IS FORECAST TO DEVELOP OVER THE SOUTHWESTERN
UNITED STATES.  IF THIS MATERIALIZES...THE RIDGE SHOULD BLOCK THE
NORTHWARD MOTION OF THE HURRICANE AND FORCE IT TO THE WEST. THIS IS
THE SOLUTION PROVIDED BY MOST OF THE TRACK AND GLOBAL MODELS.
THEREFORE...THE OFFICIAL FORECAST SLOWS BRET DOWN AND GRADUALLY
TURNS IT TO THE WEST. ON THIS TRACK...THE CENTER OF THE HURRICANE
WILL BE NEAR THE COAST WITHIN THE WARNING AREA IN ABOUT 24 TO 36
HOURS.  WEATHER CONDITIONS SHOULD BEGIN TO DETERIORATE WELL BEFORE
THAT TIME.
 
DATA CURRENTLY BEING OBTAINED BY THE NOAA GULFSTREAM JET WILL BE
USED IN THE NEXT CYCLE OF NUMERICAL MODELS.
 
AVILA
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     22/0300Z 25.2N  95.1W   115 KTS
12HR VT     22/1200Z 26.0N  95.2W   120 KTS
24HR VT     23/0000Z 26.9N  96.1W   120 KTS
36HR VT     23/1200Z 27.5N  97.3W   120 KTS...INLAND
48HR VT     24/0000Z 27.5N  97.7W    80 KTS...INLAND
72HR VT     25/0000Z 27.7N  98.5W    30 KTS...INLAND
 
 
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