000 WTNT42 KNHC 061435 TCDAT2 TROPICAL STORM PALOMA DISCUSSION NUMBER 4 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL172008 1000 AM EST THU NOV 06 2008 SATELLITE IMAGES SHOW AN ORGANIZING TROPICAL CYCLONE WITH A CENTRAL DENSE OVERCAST FEATURE DEVELOPING NEAR THE APPARENT CENTER. BANDING FEATURES ARE ALSO BECOMING MORE PROMINENT ESPECIALLY NORTH OF THE CENTER. THE INITIAL INTENSITY IS INCREASED TO 40 KT...A COMPROMISE BETWEEN OBJECTIVE AND SUBJECTIVE T-NUMBERS. AN AIR FORCE AIRCRAFT IS SCHEDULED TO BE IN THE AREA AROUND 1800Z TO PROVIDE A BETTER ESTIMATE. WARM CARIBBEAN WATERS...LIGHT SHEAR...AND PERHAPS A DEVELOPING INNER CORE STRUCTURE SHOULD FAVOR INTENSIFICATION OF THIS SYSTEM FOR THE NEXT COUPLE OF DAYS. A RAPID STRENGTHENING OF PALOMA IS ALSO POSSIBLE WITH THESE CONDITIONS AND THE SHIPS INDEX SUGGESTS THAT THE PROBABILITY OF RAPID INTENSIFICATION IS 3-4 TIMES THE CLIMATOLOGICAL AVERAGE. HOWEVER...VERTICAL WIND SHEAR IS ANTICIPATED TO BE QUITE STRONG IN 60-120 HOUR TIME PERIODS DUE TO AN APPROACHING TROUGH AND THIS SHEAR SHOULD THEN CAUSE WEAKENING. THE NHC FORECAST IS A BLEND OF THE PREVIOUS FORECAST AND THE INTENSITY FORECAST GUIDANCE. THERE IS CERTAINLY THE POSSIBILITY THAT PALOMA WOULD GET STRONGER THAN SHOWN BELOW IN BETWEEN OFFICIAL FORECAST TIMES AND IT IS WORTH NOTING THAT THE GFDL/HWRF STILL FORECAST THE STORM TO BE AT OR NEAR MAJOR HURRICANE STRENGTH IN THE CARIBBEAN SEA. BASED ON THE PREVIOUS AIRCRAFT DATA AND SATELLITE FIXES...THE INITIAL MOTION IS 340/6. THIS GENERAL MOTION...WITH A TURN TO THE NORTH TOMORROW... IS FORECAST FOR THE NEXT DAY OR SO AS THE TROPICAL CYCLONE MAKES IT WAY AROUND THE WESTERN SIDE OF RIDGING OVER THE CENTRAL CARIBBEAN. MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT AND LITTLE CHANGE WAS MADE TO THE OFFICIAL FORECAST EARLY ON. HOWEVER...THE FORECAST UNCERTAINTY INCREASES DRAMATICALLY AS PALOMA ENCOUNTERS INCREASING SOUTHWESTERLY FLOW IN THE MIDDLE- TO UPPER-LEVELS BY THE WEEKEND DUE TO A POWERFUL TROUGH MOVING INTO THE EASTERN UNITED STATES. IF THE SYSTEM REMAINS A VERTICALLY- COHERENT TROPICAL CYCLONE...PALOMA SHOULD MOVE NORTHEASTWARD ACROSS CUBA THROUGH THE BAHAMAS IN A SPEEDY FASHION...SIMILAR TO THE SOLUTIONS PROVIDED BY THE GFDL/HWRF/BAMD MODELS. HOWEVER...THE ECMWF/UKMET/NOGAPS MODELS ARE SUGGESTING THAT VERTICAL WIND SHEAR WILL RIP PALOMA APART...LEAVING THE LOW-LEVEL CIRCULATION BEHIND IN THE CARIBBEAN WHILE THE MID/UPPER-LEVEL REMNANTS SHOOT OFF TO THE NORTHEAST. WE'RE GOING TO CONTINUE THE FORECAST REASONING THAT PALOMA WILL REMAIN A STRONG AND VERTICALLY DEEP HURRICANE FOR THE NEXT SEVERAL DAYS...AND THE TRACK FORECAST LEANS TOWARD THE GFDL/HWRF/BAMD SCENARIO. HOWEVER... THE FORECAST FORWARD SPEED AFTER 72 HR WILL BE STILL BE SLOWER THAN WHAT THOSE MODELS ARE INDICATING. THE TROPICAL STORM WATCH FOR PORTIONS OF NICARAGUA AND HONDURAS WILL LIKELY BE DISCONTINUED LATER TODAY. FORECAST POSITIONS AND MAX WINDS INITIAL 06/1500Z 15.6N 82.3W 40 KT 12HR VT 07/0000Z 16.3N 82.6W 50 KT 24HR VT 07/1200Z 17.3N 82.8W 60 KT 36HR VT 08/0000Z 18.3N 82.7W 70 KT 48HR VT 08/1200Z 19.3N 82.0W 85 KT 72HR VT 09/1200Z 20.5N 80.0W 85 KT 96HR VT 10/1200Z 22.5N 76.5W 55 KT 120HR VT 11/1200Z 25.0N 73.0W 45 KT...EXTRATROPICAL $$ FORECASTER BLAKE/PASCH