000 AGXX40 KNHC 050737 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 240 AM EST WED DEC 5 2012 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... HIGH PRES OFFSHORE OF THE CAROLINAS THAT HAD DRIVEN FRESH TO STRONG WINDS IN THE SE GULF AND STRAITS OF FLORIDA OVER THE PAST SEVERAL DAYS IS WEAKENING...ALLOWING CONDITIONS TO IMPROVE. THE ASCAT PASS AROUND 0230 UTC ONLY SHOWS FRESH WINDS IN THE AREA E OF 85W. WINDS AND SEAS SHOULD CONTINUE TO DIMINISH TODAY. FARTHER W...THE COLD FRONT HAS MOVED INTO THE NW GULF AS OF THE 0600 UTC SURFACE ANALYSIS...WITH NUMEROUS MODERATE CONVECTION NOTED AHEAD OF THE FRONT. THIS FRONT IS TIED TO A SHARP MID LEVEL TROUGH THAT IS IN THE PROCESS OF SHEDDING ITS SOUTHERN ENERGY OVER THE NORTH CENTRAL GULF COAST. THIS ENERGY WILL GET LEFT BEHIND BY THE DEEP LAYER TROUGH. AT THE SURFACE...THIS WILL BE MANIFESTED BY A RAPID WEAKENING OF THE PORTION OF THE FRONT OVER THE GULF BEGINNING TONIGHT WHILE THE REMAINDER OF THE FRONT RACES EASTWARD INTO THE ATLC. THE 0000 UTC GFS...ECMWF AND UKMET LEAVE BEHIND A WELL DEFINED CIRCULATION AND DEPICT A SURFACE LOW JUST OFF THE CENTRAL LOUISIANA COAST AT 0600 UTC THIS MORNING. THE OBSERVATIONS SUPPORT A SPOT LOW ON THE NORTHERN END OF THE PRE-FRONTAL TROUGH ABOUT 100 NM TO THE NORTH OF THE 0000 UTC MODELS NEAR BATON ROUGE...LOUISIANA. THE GFS AND UKMET HOLD ONTO A STRONGER SURFACE SYSTEM LONGER IN THE FORECAST PERIOD THAN THE ECMWF...BUT THE IMPACT ON WINDS AND SEAS IS NEGLIGIBLE. THE PMDHMD FROM HPC RECOMMENDED A GFS/ECMWF BLEND. WILL KEEP WITH THAT THINKING. BY FRI...DEEP-LAYER TROUGHING BUILDING IN THE U.S. PLAINS STATES WILL ENHANCE RETURN FLOW OVER THE WESTERN GULF WITH SOUTHERLY WINDS BECOMING FRESH FRI AND SAT. BY SUN...A NEW STRONGER COLD FRONT WILL MOVE INTO TEXAS AND APPROACH THE NW GULF. THE GFS AND ECMWF AREA IN REASONABLE AGREEMENT WITH THIS PATTERN. CARIBBEAN SEA AND TROPICAL N ATLC S OF 19N W OF 55W... WEAKENING HIGH PRES OFF THE CAROLINA COAST CONTINUES TO DRIVE THE NE FLOW THROUGH THE CARIBBEAN. FRESH TO STRONG WINDS IN THE NW CARIBBEAN HAVE DIMINISHED BUT CONTINUE THIS MORNING IN THE WINDWARD PASSAGE AND THE LEE OF THE DOMINICAN REPUBLIC ACCORDING TO THE 0228 UTC ASCAT PASS AND SEVERAL SHIP OBS IN THE WINDWARD PASSAGE. THE 0000 UTC IS BETTER INITIALIZED THAN THE ECMWF WITH THESE FRESH TO STRONG WINDS. WILL BUMP THE SEAS UP IN THE WINDWARD PASSAGE SLIGHTLY COMPARED TO THE WW3...AS HAS BEEN THE CASE THE LAST FEW NIGHTS...TO BE MORE COMMISERATE WITH THE STRONG WINDS FUNNELING THROUGH THE REGION. WINDS DIMINISH LATER TODAY AND THU. BY THE WEEKEND...TRADES PICK UP ONCE AGAIN TO THE FRESH TO STRONG RANGE BETWEEN HISPANIOLA AND COLOMBIA IN THE CENTRAL CARIBBEAN AS NEW HIGH PRES BUILDS TO THE N. SW N ATLC N OF 19N W OF 55W... STRONG NE WINDS HAVE SHIFTED E OF 65W ACCORDING TO THE 0324 UTC OSCAT AND 0050 UTC ASCAT PASSES...BETWEEN TROUGHING JUST E OF THE AREA AND WEAKENING HIGH PRES OFF THE CAROLINA COAST. THE 0000 UTC GFS AND ECMWF APPEAR TO BE DOING REASONABLY WELL WITH THE WIND FIELD. THEIR CORRESPONDING WAVE MODELS APPEAR TO RUNNING ABOUT A FOOT LOWER THAN BUOYS 41046...41043... 41044...AND 41049. WINDS AND SEAS SHOULD GRADUALLY DIMINISH HERE THROUGH WED. ELSEWHERE...A NEW COLD FRONT WILL DIP INTO WATERS N OF 30N BY THU NIGHT. AT THE SAME TIME...THE INVERTED SURFACE TROUGH CURRENTLY JUST E OF THE BAHAMAS IS EXPECTED TO AMPLIFY AS THE MID LEVEL ENERGY ASSOCIATED WITH THE COLD FRONT CURRENTLY IN THE GULF OF MEXICO PASSES OVER THE AREA. THE 0000 UTC GFS AND ECMWF ARE BOTH STRONGER THAN THE OTHER MODELS WITH THIS MID LEVEL TROUGH AND SHOW A WELL AMPLIFIED SURFACE TROUGH GRADUALLY MAKING ITS WAY EASTWARD THROUGH THE BAHAMAS AND INTO FLORIDA BY FRI...PREVENTING THE COLD FRONT TO THE N FROM MOVING INTO THE AREA. A BLEND OF THE ECMWF AND GFS...AS PREFERRED BY THE HPC PMDHMD...SEEMS REASONABLE HERE. NOTE...GRIDDED MARINE FORECAST IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. SW N ATLANTIC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT WWW.HURRICANES.GOV/MARINE $$ FORECASTER SCHAUER