Hurricane WILMA

ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM
HURRICANE WILMA DISCUSSION NUMBER  35
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 PM EDT SUN OCT 23 2005

WILMA HAS CONTINUED TO BECOME BETTER ORGANIZED THIS EVENING WITH THE
LARGE 45 NMI DIAMETER BECOMING VERY DISTINCT IN BOTH SATELLITE AND
RADAR IMAGERY. AIR FORCE RECON FOUND 700 MB FLIGHT-LEVEL WINDS OF
114 KT IN THE NORTHEAST QUADRANT AT 0104Z... WHICH EQUALS ABOUT 103
KT SURFACE WINDS. DOPPLER VELOCITY DATA FROM KEY WEST HAS ALSO BEEN
AS HIGH AS 109 KT AT 12000 FT. THE CENTRAL PRESSURE HAS DECREASED
TO 958 MB... OR ABOUT 104 KT USING A STANDARD PRESSURE-WIND
RELATIONSHIP. BASED ON THIS WIND INFORMATION AND THE CONTINUED
INCREASE IN THE EYEWALL CONVECTION... THE INITIAL INTENSITY HAS
BEEN CONSERVATIVELY INCREASED TO 100 KT... OR CATEGORY THREE/MAJOR
HURRICANE STATUS. A RECON VORTEX MESSAGE JUST HANDED TO ME NOW
INDICATES THE PRESSURE HAS DECREASED TO 957 MB.
 
THE INITIAL MOTION IS 050/16. DUE TO A SLIGHT NORTHWARD TILT... THE
SURFACE CENTER HAS BEEN PLACED ABOUT ONE-TENTH OF A DEGREE SOUTH OF
THE RECON POSITIONS. WILMA HAS INCREASED ITS FORWARD SPEED BY 4 KT
DURING THE PAST 6 HOURS... AND CONTINUED ACCELERATION IS EXPECTED
FOR THE NEXT 24 HOURS. WILMA WILL LIKELY BE MOVING AT FORWARD
SPEEDS OF 20 KT OR GREATER WHEN IT REACHES THE SOUTHWESTERN FLORIDA
COAST AND CROSSES OVER THE SOUTHERN FLORIDA PENINSULA. THE NHC
MODEL GUIDANCE IS NOW TIGHTLY PACKED AROUND THE PREVIOUS FORECAST
TRACK... SO NO SIGNIFICANT CHANGES WERE MADE OTHER THAN TO INCREASE
FORWARD SPEED AT ALL TIMES... ESPECIALLY AFTER WILMA EMERGES OVER
THE WESTERN ATLANTIC. IN THE SHORT TERM... WATER VAPOR IMAGERY...
00Z UPPER-AIR DATA... AND DROPSONDE DATA FROM THE NOAA G-IV JET
AIRCRAFT INDICATE THE DEEP LAYER TROUGH OVER THE CENTRAL U.S. HAS
EXTENDED ITS INFLUENCE INTO THE WESTERN AND CENTRAL GULF OF MEXICO.
WESTERLY MID-LEVEL WINDS OF 15-20 KT ARE NOW IMPINGING ON THE
WESTERN SIDE OF WILMA... SO A CONTINUED NORTHEASTWARD MOTION TOWARD
THE SOUTHWEST FLORIDA COAST AND ACROSS THE SOUTHERN FLORIDA SEEMS
LIKELY. THEREFORE... A TRACK FROM COLLIER COUNTY TO NEAR LAKE
OKEECHOBEE AND EXITING PALM BEACH COUNTY DURING THE NEXT 18 HOURS
SEEMS QUITE REASONABLE. HOWEVER... GIVEN THAT WILMA HAS A 40-50 NMI
DIAMETER EYE... HURRICANE-FORCE WINDS WILL EXTEND WELL AWAY FROM
WHERE THE EXACT CENTER PASSES. IN THE LONGER TERM... ONCE WILMA
EMERGES OVER THE ATLANTIC... THE DEEP LAYER TROUGH IS FORECAST TO
CONTINUE DIGGING SHARPLY SOUTHWARD OVER THE SOUTHEASTERN U.S. AND
THE GULF OF MEXICO. THIS SHOULD ACT TO LIFT WILMA RAPIDLY NORTHEAST
TO NORTH-NORTHEASTWARD AND CONTINUE TO ACCELERATE THE HURRICANE OFF
THE U.S. EAST COAST... WITH A POSSIBLE SECOND LANDFALL OCCURRING
OVER NOVA SCOTIA AS A POWERFUL AND VERY LARGE EXTRATROPICAL LOW
PRESSURE SYSTEM. THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE
PREVIOUS FORECAST... AND IS CLOSE TO THE NHC GUNA CONSENSUS MODEL.

NOW THAT WILMA HAS ACCELERATED NORTHEASTWARD... THE EFFECTS OF ANY
UPPER-LEVEL SHEAR SHOULD BE MINIMIZED RIGHT UP UNTIL THE HURRICANE
REACHES THE FLORIDA EAST COAST. THE VARIOUS GLOBAL MODELS INDICATE
THE DUAL OUTFLOW CHANNELS SHOULD REMAIN INTACT UNTIL WILMA REACHES
THE ATLANTIC OCEAN... WHICH FAVOR AT LEAST SUSTAINING THE CURRENT
INTENSITY. EYES THIS LARGE ARE ALSO MORE STABLE AND ARE MORE
RESISTANT TO VERTICAL SHEAR. AS SUCH... WILMA IS EXPECTED TO BE A
MAJOR HURRICANE AT LANDFALL ALONG THE SOUTHWEST FLORIDA COAST EARLY
MONDAY MORNING.  HOWEVER... ANOTHER 5-KT INCREASE IN INTENSITY MAY
OCCUR WHILE WILMA REMAINS OVER THE SLIGHTLY WARMER GULF LOOP
CURRENT. GIVEN THE FAST FORWARD SPEED EXPECTED AS WILMA TRAVERSES
THE SOUTHERN FLORIDA PENINSULA... LESS WEAKENING SHOULD OCCUR AS
COMPARED TO TYPICAL HURRICANES MOVING OVER LAND. THEREFORE... WILMA
IS EXPECTED TO BE A CATEGORY TWO HURRICANE WHEN IT REACHES THE
FLORIDA EAST COAST. AFTER EMERGING OVER THE ATLANTIC... INCREASING
VERTICAL SHEAR IN EXCESS OF 50 KT AND MERGER WITH A FRONTAL SYSTEM
SHOULD RESULT IN WILMA TRANSITIONING INTO A SIGNIFICANT
EXTRATROPICAL WINTER-TYPE STORM SYSTEM... WHICH MAY PRODUCE A LARGE
GALE AREA ON THE WEST SIDE OF THE STORM THAT COULD AFFECT PORTIONS
OF THE U.S. EAST COAST AND THE CANADIAN MARITIMES.
 
FORECASTER STEWART
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      24/0300Z 24.4N  83.7W   100 KT
 12HR VT     24/1200Z 26.2N  81.2W   100 KT...INLAND SWRN FLORIDA
 24HR VT     25/0000Z 30.2N  76.3W    75 KT...OVER ATLANTIC
 36HR VT     25/1200Z 36.5N  69.9W    65 KT...BECOMING EXTRATROPICAL
 48HR VT     26/0000Z 42.9N  64.7W    60 KT...EXTRATROPICAL
 72HR VT     27/0000Z 48.0N  60.0W    55 KT...EXTRATROPICAL
 96HR VT     28/0000Z 49.5N  49.5W    55 KT...EXTRATROPICAL
120HR VT     29/0000Z 50.0N  38.0W    55 KT...EXTRATROPICAL
 
$$
NNNN