Hurricane Isabel

Forecast Advisory 21

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000
WTNT33 KNHC 110839
TCPAT3
BULLETIN
HURRICANE ISABEL ADVISORY NUMBER 21
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM AST THU SEP 11 2003

...POWERFULL HURRICANE ISABEL ON A WESTWARD TRACK...

AT 5 AM AST...0900Z...THE EYE OF HURRICANE ISABEL WAS LOCATED NEAR
LATITUDE 21.3 NORTH...LONGITUDE 53.7 WEST OR ABOUT 650 MILES...
1050 KM...EAST-NORTHEAST OF THE NORTHERN LEEWARD ISLANDS.

ISABEL IS MOVING TOWARD THE WEST NEAR 10 MPH...17 KM/HR. THIS
GENERAL MOTION IS EXPECTED TO CONTINUE DURING THE NEXT 24 HOURS.

ISABEL IS A POWERFULL CATEGORY FOUR HURRICANE ON THE SAFFIR/SIMPSON
HURRICANE SCALE WITH MAXIMUM SUSTAINED WINDS OF NEAR 145 MPH...230
KM/HR...AND HIGHER GUSTS. LITTLE OVERALL CHANGE IN STRENGTH IS
FORECAST DURING THE NEXT 24 HOURS. HOWEVER...FLUCTUATIONS IN
INTENSITY ARE COMMON IN MAJOR HURRICANES.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM...
FROM THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP
TO 185 MILES...295 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 936 MB...27.64 INCHES.

LARGE OCEAN SWELLS MAY CREATE HAZARDOUS SURF CONDITIONS IN THE
LEEWARD ISLANDS.

REPEATING THE 5 AM AST POSITION...21.3 N... 53.7 W. MOVEMENT
TOWARD...WEST NEAR 10 MPH. MAXIMUM SUSTAINED WINDS...145 MPH.
MINIMUM CENTRAL PRESSURE... 936 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
11 AM AST.

FORECASTER AVILA