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HURRICANE GERT DISCUSSION NUMBER  33
NATIONAL WEATHER SERVICE MIAMI FL
11 AM EDT SUN SEP 19 1999

GERT DOES NOT LOOK QUITE AS IMPRESSIVE AS IT DID EARLIER.  THE
AMOUNT OF COLD CLOUD TOPS IN THE CDO HAS DECREASED AND THE EYE IS
NOT THAT WELL-DEFINED.  UPPER-TROPOSPHERIC OUTFLOW IS RESTRICTED TO
THE SOUTHWEST.  NONETHELESS...IT IS A FORMIDABLE HURRICANE WITH A 30
N MI DIAMETER EYE AND A CLOSED WALL AS SUGGESTED BY MICROWAVE
IMAGERY DATA.  THE STATISTICAL INTENSITY PREDICTION SCHEME SHOWS
GERT MAINTAINING MAJOR HURRICANE STRENGTH FOR THE NEXT FEW DAYS...AS
DOES THE NHC INTENSITY FORECAST.

INITIAL MOTION...320/7...IS ABOUT THE SAME AS IN THE PREVIOUS
ADVISORY.  GERT HAS TRACKED A BIT TO THE LEFT OF YESTERDAYS MOTION. 
THIS IS LIKELY DUE TO THE COMBINATION OF MORE DEEP-LAYER RIDGING TO
THE NORTH OF THE HURRICANE AND STEERING AROUND A WEAK MID/UPPER
LEVEL CYCLONE JUST NORTHEAST OF PUERTO RICO.  HOWEVER A LARGE 500 MB
TROUGH IS PREDICTED TO BE OVER THE U.S. EAST COAST IN A COUPLE OF
DAYS...AND THIS SHOULD WEAKEN THE SUBTROPICAL RIDGE.  AS A
CONSEQUENCE...GERT IS LIKELY TO TURN NORTHWARD GRADUALLY.  THE
OFFICIAL FORECAST TRACK IS SIMILAR TO THE PREVIOUS ONE AND NEAR THE
WESTERN EDGE OF THE GUIDANCE ENVELOPE.

PASCH

FORECAST POSITIONS AND MAX WINDS
 
INITIAL     19/1500Z 24.9N  59.5W   115 KTS
12HR VT     20/0000Z 25.7N  60.2W   115 KTS
24HR VT     20/1200Z 27.3N  61.5W   115 KTS
36HR VT     21/0000Z 29.0N  62.5W   110 KTS
48HR VT     21/1200Z 31.0N  62.5W   105 KTS
72HR VT     22/1200Z 36.0N  61.0W   100 KTS
 
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