Thursday, October 20, 2005

Wilma: 'Round'n'round she goes - "Low confidence forecast"


Image source: National Hurricane Center / NOAA


Well, this about sums it up.

The National Hurricane Center gives you the straight dope -- at this point, it's just about anyone's guess where this mother will end up.

"C'mon! Papa needs a new pair of shoes!"

Toss the dice... More tomorrow.



000
WTNT44 KNHC 210254
TCDAT4
HURRICANE WILMA DISCUSSION NUMBER 23
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
11 PM EDT THU OCT 20 2005

REPORTS FROM A NOAA HURRICANE HUNTER AIRCRAFT BEFORE 00Z INDICATED
THAT THE CENTRAL PRESSURE OF WILMA HAD RISEN TO 923 MB...AND THE
MAXIMUM 700 MB FLIGHT-LEVEL WINDS HAD DECREASED TO 130-140 KT.
SINCE THEN...SATELLITE IMAGERY SHOWS AN IMPROVED EYE PRESENTATION
AND COOLING CLOUD TOPS AROUND THE CENTER..ALTHOUGH NOT ENOUGH TO
JUSTIFY AN INCREASE IN INTENSITY. BASED ON THIS...THE INITIAL
INTENSITY REMAINS 130 KT. THE NEXT AIRCRAFT WILL INVESTIGATE WILMA
AROUND 05Z.

WILMA HAS TURNED MORE TO THE RIGHT DURING THE PAST FEW HR...WITH THE
INITIAL MOTION NOW 325/5. THE HURRICANE IS MOVING INTO A COL AREA
BETWEEN MID-LEVEL RIDGES TO THE EAST AND WEST...WHILE THE STRONGER
WESTERLIES REMAIN NORTH OF 26N ACCORDING TO DATA FROM THE NOAA G4
JET. THIS IS A GOOD FORMULA FOR SLOW MOTION...AND ALL MODELS AGREE
ON THIS FOR THE NEXT 24-48 HR. HOWEVER...THE DYNAMICAL MODELS
STEER WILMA NORTHWESTWARD INTO THE YUCATAN PENINSULA DURING THE
NEXT 12-24 HR...A MOTION THAT IS NOT SUPPORTED BY THE CURRENT RIGHT
TURN OR THE JET DATA. THEREFORE...THE FORECAST TRACK WILL BE WELL
TO THE RIGHT OF THE MODEL GUIDANCE...WITH THE CENTER FORECAST TO
PASS OVER THE EXTREME NORTHEASTERN TIP OF THE YUCATAN PENINSULA.
THIS TRACK ALSO REQUIRES AN EARLIER RECURVATURE INTO THE WESTERLIES
THAN ANY OF THE GUIDANCE AND A FASTER PROGRESS TOWARD THE NORTHEAST
AND THE FLORIDA PENINSULA. THE NEW FORECAST TRACK IS SIMILAR TO
THE PREVIOUS FORECAST...EXCEPT SOMEWHAT SLOWER THROUGH 96 HR.
GIVEN THE RADICAL DEPARTURE FROM THE MODEL GUIDANCE...THIS IS A LOW
CONFIDENCE FORECAST.

THE INTENSITY FORECAST IS VERY PROBLEMATIC. FIRST...THE INTENSITY
FORECAST CALLS FOR WEAKENING DUE TO PASSAGE OVER THE YUCATAN
PENINSULA. IF WILMA MOVES AS FAR INLAND AS THE MODELS FORECAST...
IT WILL WEAKEN CONSIDERABLY AND LIKELY BE MUCH WEAKER THAN FORECAST
ALONG THE REST OF THE TRACK. ON THE OTHER HAND...IF THE EYE MOVES
EAST OF THE TRACK THE HURRICANE WILL LIKELY STAY STRONGER THAN
FORECAST...AT LEAST FOR THE FIRST 36-48 HR. SECOND...ALL AVAILABLE
DATA SHOWS THAT THE OUTFLOW HAS DECREASED TO THE WEST AS WEAK
WESTERLY FLOW IMPINGES ON WILMA. THIS WILL LIKELY NOT PREVENT THE
INTENSIFICATION FORECAST DURING THE NEXT 24 HR...ALTHOUGH IT MAY BE
A PRECURSOR TO THE SHEAR FORECAST TO AFFECT THE HURRICANE OVER THE
GULF OF MEXICO. THIS SHEAR SHOULD CAUSE WILMA TO WEAKEN REGARDLESS
OF HOW STRONG IT IS AFTER PASSING YUCATAN. THIRD...WATER VAPOR
IMAGERY CONTINUES TO SHOW VERY DRY MID/UPPER-LEVEL AIR COVERING THE
GULF OF MEXICO. AS WILMA INTERACTS WITH THE WESTERLIES...THIS AIR
SHOULD BEGIN TO ENTRAIN INTO THE HURRICANE...AND INDEED THERE HAS
BEEN SOME EROSION OF THE WESTERN SIDE OF THE CLOUD PATTERN DURING
THE PAST 6 HR. FINALLY...WILMA SHOULD PASS OVER THE WARM LOOP
CURRENT FOLLOWED BY COOLER WATERS NEAR THE FLORIDA PENINSULA. THE
LATTER SHOULD AID THE SHEAR-INDUCED WEAKENING. GIVEN THE
UNCERTAINTIES...THE INTENSITY FORECAST WILL CHANGE LITTLE FROM THE
PREVIOUS ADVISORY. IT SHOULD BE NOTED THAT IF WILMA MISSES YUCATAN
THERE IS A CHANCE THAT IN SPITE OF ALL THE NEGATIVE FACTORS IT
COULD BE A MAJOR HURRICANE AT LANDFALL IN FLORIDA.

NOAA BUOY 42003 IN THE EASTERN GULF OF MEXICO REPORTS THAT LARGE
SWELLS GENERATED BY WILMA ARE PROPAGATING TOWARD PORTIONS OF THE
NORTHERN GULF COAST...AND COULD REACH THE COAST ON FRIDAY.

FORECASTER BEVEN


FORECAST POSITIONS AND MAX WINDS

INITIAL 21/0300Z 19.3N 86.0W 130 KT
12HR VT 21/1200Z 19.9N 86.4W 140 KT
24HR VT 22/0000Z 20.8N 87.0W 145 KT...INLAND
36HR VT 22/1200Z 21.5N 87.1W 120 KT...INLAND
48HR VT 23/0000Z 22.1N 86.7W 105 KT...OVER WATER
72HR VT 24/0000Z 23.5N 84.5W 95 KT
96HR VT 25/0000Z 27.5N 79.5W 65 KT
120HR VT 26/0000Z 38.5N 69.5W 60 KT...EXTRATROPICAL


$$





posted by Fergie @ 10/20/2005 08:11:00 PM

0 Comments:

Post a Comment

<< Home