000 AGXX40 KNHC 262023 CCA MIMATS MARINE WEATHER DISCUSSION...CORRECTED NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 200 PM EST THU NOV 26 2009 CORRECTED ISSUANCE TIME MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... THE SLOW MOVING FRONTAL BOUNDARY CURRENTLY PUSHING THROUGH THE STRAITS OF FL AND YUCATAN CHANNEL WILL FINALLY MOVE SE OF THE GULF TONIGHT. SURFACE OBSERVATIONS AND THE 1600 UTC ASCAT PASS SHOW 20 KT WINDS OVER MUCH OF THE GULF...WITH THE STRONGEST WINDS WITHIN 120 NM N OF THE FRONT OVER THE CENTRAL GULF. RECENT SHIP OBSERVATIONS SHOW SIGNIFICANT WAVE HEIGHT HAVE BUILT TO THE 10 TO 14 FT RANGE HERE AS WELL. NORTHERLY FLOW IN THE SW GULF...WHICH HAD BEEN IN THE 25 TO 30 KT RANGE OVERNIGHT...WILL DIMINISH OVER THE NEXT 24 HOUR AND SHIFT EASTERLY AS THE HIGH PRES RIDGE OVER THE WESTERN GULF SHIFTS TO THE NORTHEAST....REACHING NORTH FLORIDA LATE SAT WITH RIDGE OVER THE NORTHEAST GULF OF MEXICO SUN. RIDGE WILL WEAKEN MON AS A COLD FRONT MOVES OFF THE TEXAS COAST. THE MODELS ARE IN GOOD AGREEMENT UNTIL THIS POINT WHEN THE GFS...UKMET...AND CMC CARRY A WEAK SURFACE LOW THROUGH THE NORTHERN GULF MON NIGHT AND DRAG THE FRONT EASTWARD FASTER THAN THE NOGAPS AND ECMWF. DESPITE THESE DIFFERENCES...THE MODELS ARE COMING INTO BETTER AGREEMENT HERE...TRENDING TOWARD A SLOWER SOLUTION HERE MORE LIKE THE ECMWF. CARIBBEAN AND TROPICAL N ATLC... THE SLOW MOVING FRONTAL BOUNDARY CURRENTLY OVER THE FAR NW CARIBBEAN IS BRINGING 20 KT N FLOW INTO THE GULF OF HONDURAS BEHIND THE FRONT ACCORDING TO THE 1600 UTC ASCAT PASS. THE FRONT IS FORECAST TO CONTINUE TO SLOWLY SHIFT EASTWARD OVER THE NEXT FEW DAYS AND DISSIPATE. THE MODELS ARE IN REASONABLE AGREEMENT ON WINDS AND SEAS DIMINISHING BELOW 20 KT/8 FT BY SUN. THEN...LOOK FOR WINDS TO SHIFT MORE SOUTHERLY IN ADVANCE OF THE STRONG COLD FRONT IN THE GULF OF MEXICO EARLY NEXT WEEK. FARTHER SOUTH...THE PRES GRADIENT BETWEEN THE 1017 MB HIGH NEAR 26N62W AND THE 1005 MB COLOMBIAN LOW CONTINUES TO SUPPORT WINDS IN THE 25-30 KT RANGE AS SEEN IN SHIP OBSERVATIONS FROM SHIP DHER AND AND 9HXD9 OVER THE PAST FEW HOURS. HIGH PRES TO THE NORTH WILL BE FORCED E AS THE COLD FRONT OVER THE SW N ATLC ZONE PUSHES EASTWARD...DECREASING THE PRES GRADIENT AND THE WINDS OVER THE CENTRAL CARIBBEAN INTO SAT...BUT LOOK FOR WINDS TO BUILD AGAIN BY SUN AS NEW HIGH PRES MOVES IN BEHIND THE SW N ATLC COLD FRONT. THIS HIGH PRES WILL BE CHASED E EARLY NEXT WEEK BY THE COLD FRONT ADVANCING THROUGH THE GULF OF MEXICO. FARTHER E OVER THE TROPICAL ATLC...A SLOW MOVING DEEP LAYER TROUGH ALONG 50-55W WILL CONTINUE TO SUPPORT A WEAK SURFACE TROUGH S OF 20N INTO THE WEEKEND...AND TRADE WINDS OVER 20 KT AND MUCH OF THE CONVECTION ASSOCIATED WITH THE SYSTEM WILL MAINLY BE CONFINED E OF THIS TROUGH KEEPING CONDITIONS RELATIVELY TRANQUIL OVER THE LESSER ANTILLES THROUGH THE WEEKEND. THE WEAK FRONTAL BOUNDARY ASSOCIATED WITH THE FRONT CURRENTLY OVER THE SW N ATLC WILL APPROACH THE NE CARIBBEAN ISLANDS EARLY NEXT WEEK AND MAY ENHANCE THE CHANCE OF CONVECTION. SW N ATLC... NEITHER THE 1500 UTC SREF OR 1200 UTC GEFS MEMBERS SUPPORT WINDS TO GALE FORCE NEAR THE FRONT PASSING THROUGH THE SW N ATLC FRI AND SAT...BUT THE DETERMINISTIC RUNS GENERALLY SUPPORT WINDS TO 30 KT HERE IN THE SOUTHERLY FLOW AHEAD OF THE FRONT. THE 1420 UTC ASCAT PASS ALREADY SHOWS SOUTHERLY FLOW IN THE 20-25 KT RANGE OVER N CENTRAL WATERS. ONCE THE UPPER LEVEL TROUGH CATCHES UP TO THIS SURFACE BOUNDARY...LOOK FOR THE FRONT TO PICK UP SPEED...MOVING THROUGH THE REMAINDER OF THE SW N ATLC ZONE BY SAT NIGHT. THE MODELS ARE IN REASONABLY GOOD AGREEMENT WITH THE PASSAGE OF THIS FRONTAL SYSTEM THROUGH THE ZONE AS WELL AS WITH THE TIMING AND TRACK OF THE HIGH PRES SYSTEM IN ITS WAKE. DIFFERENCES ARISE WITH THE TIMING OF THE NEXT COLD FRONT MOVING INTO NW WATERS TUE...WITH THE GFS AND ECMWF PREFERRING A SLOWER SOLUTION THAN THE OTHER MODELS. THE ECMWF IS PREFERRED IN THE GULF AS EXPLAINED IN THE FIRST SECTION ABOVE. OTHERWISE WINDS WILL BE LESS THAN 20 KT. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. $$ FORECASTER SCHAUER