000
WTPZ43 KNHC 220842
TCDEP3
TROPICAL STORM GENEVIEVE DISCUSSION NUMBER   4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP082008
200 AM PDT TUE JUL 22 2008
 
A 0054 UTC QUIKSCAT AMBIGUITY ANALYSIS REVEALED A FEW PLAUSIBLE...
ALBEIT RAIN-FLAGGED WIND VECTORS AS HIGH AS 40 KT NEAR THE
CIRCULATION CENTER. IN ADDITION...SATELLITE INTENSITY ESTIMATES
FROM BOTH TAFB AND SAB HAVE INCREASED TO T3.0 SO THE INITIAL
INTENSITY WILL BE SET AT 40 KT.
 
GENEVIEVE WAS MOVING FAIRLY QUICKLY TO THE WEST-NORTHWEST ALTHOUGH
IT NOW APPEARS IT MAY BE STARTING TO SLOW DOWN WITH AN INITIAL
MOTION OF 285/13. THE DECREASE IN SPEED IS EXPECTED TO CONTINUE
OVER THE NEXT DAY OR SO AS THE WEAK MID-LEVEL RIDGE OVER NORTHEAST
MEXICO SHIFTS FARTHER NORTH ACROSS THE SOUTHERN ROCKIES.
THEREAFTER...THE SUITE OF DYNAMICAL MODEL GUIDANCE IS NOW SHOWING
GREATER SPREAD AND UNCERTAINTY AT THE DAY 3-5 PERIODS ALTHOUGH
THERE IS A NOTICEABLE SOUTHWARD SHIFT COMPARED WITH PREVIOUS
FORECAST CYCLES. AS A RESULT...THE OFFICIAL FORECAST IS SHIFTED
SOUTHWARD BUT STILL LIES ON THE NORTHERN EDGE OF THE CLUSTER OF
DYNAMICAL MODELS.

GENEVIEVE IS VERY NEAR THE EASTERN EDGE OF THE COLD WAKE GENERATED
BY TROPICAL STORM FAUSTO AND WILL REMAIN OVER THIS FEATURE DURING
THE NEXT 48 HOURS OR SO. SHIPS IS STILL THE ONLY MODEL THAT
STRENGTHENS GENEVIEVE TO A HURRICANE...BUT SINCE IT DOES NOT
RECOGNIZE THE COLD WAKE...IT MAY BE RELYING ON SST DATA THAT IS UP
TO 5C TOO WARM. THEREFORE...THE NEW INTENSITY FORECAST KEEPS THE
CYCLONE JUST BELOW HURRICANE STRENGTH BY ASSUMING THE STORM WILL
HAVE A DIFFICULT TIME STRENGTHENING MUCH OVER THE COOLER WATERS.
THIS IS IN BETTER AGREEMENT WITH THE OTHER INTENSITY MODELS...SOME
OF WHICH BARELY GIVE GENEVIEVE A FIGHTING CHANCE.

FORECAST POSITIONS AND MAX WINDS
 
INITIAL      22/0900Z 14.6N 105.2W    40 KT
 12HR VT     22/1800Z 15.0N 106.9W    45 KT
 24HR VT     23/0600Z 15.4N 108.8W    50 KT
 36HR VT     23/1800Z 15.8N 110.6W    50 KT
 48HR VT     24/0600Z 16.0N 112.3W    55 KT
 72HR VT     25/0600Z 16.0N 115.0W    60 KT
 96HR VT     26/0600Z 16.0N 117.5W    50 KT
120HR VT     27/0600Z 16.0N 120.5W    40 KT
 
$$
FORECASTER BERG/RHOME