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TROPICAL STORM ALLISON SPECIAL DISCUSSION NUMBER   1
NATIONAL WEATHER SERVICE MIAMI FL
3 PM EDT TUE JUN 05 2001
 
REPORTS FROM AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT INDICATE
THAT THE TROPICAL DISTURBANCE OVER THE NORTHWEST GULF OF MEXICO HAS
A BROAD CLOSED LOW-LEVEL CIRCULATION.  AS A RESULT OF THE 40 TO 50
KT SURFACE WINDS ON THE EAST SIDE...THE SYSTEM IS BEING UPGRADED
DIRECTLY TO THE FIRST TROPICAL STORM OF THE ATLANTIC SEASON JUST OFF
THE SOUTHEAST TEXAS COAST.
 
INITIAL MOTION ESTIMATE IS 360/11.  TROPICAL STORM ALLISON IS
EXPECTED TO TRACK NORTHWARD ALONG THE WESTERN PERIPHERY OF THE
SUBTROPICAL RIDGE WHOSE AXIS IS LOCATED EAST-WEST ACROSS THE
SOUTHERN U.S. FROM GEORGIA TO LOUISIANA. THE BROAD CENTER SHOULD
MOVE INLAND OVER EXTREME SOUTHEAST TEXAS OR SOUTHWEST LOUISIANA
LATER TONIGHT AND THEN TURN MORE TOWARD THE NORTHEAST AS A SHORTWAVE
TROUGH OVER THE SOUTHERN PLAINS GRADUALLY PICKS UP THE SYSTEM.  THIS
SCENARIO IS CONSISTENT WITH MOST OF THE DYNAMICAL MODEL GUIDANCE.
 
SOME SLIGHT STRENGTHENING IS POSSIBLE BEFORE LANDFALL EVEN THOUGH
ALLISON IS MORE LIKE A HYBRID SYSTEM.  HOWEVER...IT IS UNLIKELY THAT
THE CYCLONE WOULD GET ABOVE 55 KT BEFORE DUE TO THE COOL OFFSHORE
SEA SURFACE TEMPERATURES.
 
FORECASTER STEWART
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     05/1900Z 28.3N  94.7W    50 KTS
12HR VT     06/0600Z 30.1N  94.2W    45 KTS...INLAND
24HR VT     06/1800Z 31.6N  93.9W    30 KTS...INLAND DISSIPATING
36HR VT     07/0600Z 33.1N  93.2W    25 KTS...INLAND DISSIPATING
48HR VT     07/1800Z 34.4N  92.0W    20 KTS...INLAND DISSIPATING
 
 
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