ZCZC MIATCDAT3 ALL
TTAA00 KNHC DDHHMM
HURRICANE GABRIELLE DISCUSSION NUMBER 22
NATIONAL WEATHER SERVICE MIAMI FL
11 PM EDT SUN SEP 16 2001
A NOAA AIRCRAFT GPS DROPSONDE MEASURED 68 KNOTS NEAR THE CENTER JUST
ABOVE THE SURFACE AT ABOUT 00Z. GABRIELLE IS UPGRADED TO 65
KNOTS...A HURRICANE...ON THIS BASIS. THE SYSTEM LOOKS HIGHLY
SHEARED AND ASYMMETRIC WITH DEEP CONVECTION NORTH AND EAST OF THE
CENTER. IS THE SYSTEM STILL TROPICAL? PERHAPS. ACCORDING TO THE
PENN STATE CYCLONE PHASE ANALYSIS FROM THE 12Z AVIATION MODEL...THE
TEMPERATURE STRUCTURE IS NEAR NEUTRAL. SO WE WILL HOLD ON TO
TROPICAL STATUS FOR A WHILE LONGER. ONLY SLIGHT WEAKENING IS
FORECAST DURING THE NEXT 72 HOURS FOLLOWING THE SHIPS MODEL. IN
CONTRAST THE GFDL AND UKMET FORECAST SIGNIFICANT STRENGTHENING.
THE INITIAL MOTION AND FORECAST TRACK ARE A LITTLE LEFT OF THE
PREVIOUS ADVISORY. OTHERWISE THERE IS NO CHANGE IN PHILOSOPHY FROM
THE PREVIOUS ADVISORY. GABRIELLE IS EMBEDDED IN THE WESTERLIES AND
ALL OF THE GUIDANCE IS IN GOOD AGREEMENT ABOUT A CONTINUED
EAST-NORTHEAST TRACK FOR THE NEXT 72 HOURS.
SHIP REPORTS AND QUIKSCAT DATA ARE THE BASIS FOR EXPANDING THE
34-KNOT WIND RADII.
THE GALE WARNING FOR BERMUDA IS CHANGED TO A TROPICAL STORM WARNING.
FORECASTER LAWRENCE
FORECAST POSITIONS AND MAX WINDS
INITIAL 17/0300Z 33.6N 70.5W 65 KTS
12HR VT 17/1200Z 34.8N 67.7W 65 KTS...EXTRATROPICAL
24HR VT 18/0000Z 36.5N 64.5W 60 KTS...EXTRATROPICAL
36HR VT 18/1200Z 38.0N 62.0W 60 KTS...EXTRATROPICAL
48HR VT 19/0000Z 39.5N 59.5W 60 KTS...EXTRATROPICAL
72HR VT 20/0000Z 44.0N 53.0W 50 KTS...EXTRATROPICAL
NNNN
Problems?