Hurricane GORDON

ZCZC MIATCDAT2 ALL
TTAA00 KNHC DDHHMM
HURRICANE GORDON DISCUSSION NUMBER  22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL072006
500 AM EDT SAT SEP 16 2006
 
ONLY LIMITED DEEP CONVECTION IS OCCURRING AROUND THE NOW RAGGED EYE
SEEN IN INFRARED IMAGERY.  SUBJECTIVE DVORAK DATA-T NUMBERS FROM
TAFB AND SAB ARE 3.5 AND 4.0...AND GIVEN THIS...THE INTENSITY IS
LOWERED TO 65 KT.  GORDON WILL CONTINUE TO WEAKEN SLOWLY OVER THE
NEXT DAY OR TWO AS IT CROSSES THE 27C ISOTHERM AND MOVES OVER
PROGRESSIVELY COOLER WATERS.  THE GLOBAL MODELS INDICATE THAT
GORDON WILL BECOME EXTRATROPICAL BETWEEN DAYS 2 AND 3...AND THE
INTENSITY IS HELD AT 50 KT ASSUMING THAT THE CYCLONE RECEIVES A
SHOT OF BAROCLINIC ENERGY LATE IN THE PERIOD. THE
GFS...UKMET...CANADIAN...ECMWF...AND GFDL MODELS ALL SHOW GORDON
BECOMING ABSORBED INTO A FRONTAL SYSTEM BY DAY 4 OR 5. ONLY THE
NOGAPS KEEPS GORDON AS A SEPARATE SYSTEM WELL TO THE SOUTH OF THE
REST OF THE GUIDANCE...A SOLUTION THAT SEEMS UNLIKELY GIVEN THE
NOGAPS MODEL ROBUST BOGUS. THE CURRENT FORECAST INDICATES
EXTRATROPICAL TRANSITION BY DAY 3 AND ABSORPTION BY THE FRONT AT
DAY 4.
 
GORDON HAS BEEN MOVING ERRATICALLY OVER THE PAST FEW HOURS...AND NOW
APPEARS TO BE NEARLY STATIONARY OR EVEN DRIFTING SLIGHTLY WEST.
THE GLOBAL MODELS ALL SHOW A SLOW NORTHWARD MOTION OVER THE NEXT 12
HOURS.  THEREAFTER...A TURN TO THE NORTHEAST AND INCREASE IN
FORWARD SPEED IS EXPECTED AHEAD OF A MID-LATITUDE TROUGH MOVING
OFFSHORE OF THE EASTERN UNITED STATES. THE CONSENSUS OF THE GLOBAL
MODELS AND THE GFDL...AND THE FSU SUPERENSEMBLE ARE LEFT OF AND
SLOWER THAN THE PREVIOUS FORECAST THROUGH 48 HOURS. AN INCREASE IN
MODEL SPREAD IS SEEN AT DAY 3 AS THE CYCLONE ACCELERATES TOWARD THE
EAST-NORTHEAST. THE OFFICIAL FORECAST IS BETWEEN THE PREVIOUS
FORECAST AND THE GLOBAL MODEL CONSENSUS AND THE FORWARD SPEED
CLOSELY FOLLOWS THE TREND OF THE DYNAMICAL MODEL CONSENSUS...
CONU...AND THE FSU SUPERENSEMBLE.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      16/0900Z 31.3N  53.7W    65 KT
 12HR VT     16/1800Z 32.0N  53.3W    65 KT
 24HR VT     17/0600Z 33.2N  52.7W    60 KT
 36HR VT     17/1800Z 35.1N  51.2W    55 KT
 48HR VT     18/0600Z 37.3N  48.0W    55 KT
 72HR VT     19/0600Z 40.5N  35.5W    50 KT...EXTRATROPICAL
 96HR VT     20/0600Z...ABSORBED BY FRONTAL SYSTEM
 
$$
FORECASTER BRENNAN/KNABB
 
NNNN