000 AGXX40 KNHC 170736 CCA MIMATS MARINE WEATHER DISCUSSION...CORRECTED NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 235 AM EST SUN JAN 17 2010 CORRECTED FOR WARNING IN STRAITS OF FL... MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... WINDS HAVE DIMINISHED BELOW GALE FORCE AHEAD OF THE FRONT OVER THE NORTHERN GULF...BUT THERE ARE SEVERAL REPORTS OVER GALE FORCE FOUND IN THE STRAITS OF FLORIDA...SO THE GALE FLAG WILL BE HOISTED FOR THE BRIEF PERIOD THIS MORNING BEFORE THE COLD FRONT PASSES THROUGH. WINDS WILL DROP BELOW 20 KT RAPIDLY ACROSS THE WESTERN AND CENTRAL GULF TODAY AS THE FRONT PUSHES THROUGH FLORIDA AND HIGH PRES MOVES IN ALONG THE COASTAL PLAIN. THE MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH THE TIMING OF THE COLD FRONT AND THE HIGH PRES BEHIND IT. THE HIGH SHIFTS INTO THE EASTERN GULF TUE AS A NEW SYSTEM EMERGES IN THE PLAINS. EXPECT THE SOUTHERLY RETURN FLOW TO PICK UP TO 20 KT IN THE WESTERN GULF TUE NIGHT AS A RESULT OF THE INCREASED PRES GRADIENT. THE MODELS AGREE ON TURNING THE UPPER LEVEL FLOW MORE ZONAL AND PROGRESSIVE...BUT DIVERGE WITH THEIR HANDLING OF THE SYSTEM PASSING FROM THE PLAINS THROUGH THE MISSISSIPPI VALLEY AND INTO THE SOUTHEAST TUE THROUGH THU. THE GFS IS THE FASTEST SOLUTION AND IT IS FAVORED CONSIDERING THE AGREEMENT AMONGST THE MODELS ON A MORE PROGRESSIVE STEERING PATTERN. HOWEVER...THERE IS SOME CONCERN THAT THE GFS IS AGAIN HAVING CONVECTIVE FEEDBACK PROBLEMS THAT ARE CAUSING ITS SURFACE DEPICTION TO BE TOO WRAPPED UP...MAKING ITS WIND FIELD TOO STRONG AND IMPACTING THE WW3 OUTPUT BY INCREASING THE SIGNIFICANT WAVE HEIGHTS IN THE GULF MORE THAN WHAT IS LIKELY. THE GFS CARRIES A 1000 MB LOW OVER SOUTHERN MISSISSIPPI AT 0600 UTC THU AND DUMPS OVER 4 INCHES OF PRECIPITATION OVER THE AREA IN THE PRECEDING 6 HOURS. THEN...THE GFS DEEPENS THE LOW TO 997 MB AS IT PASSES THROUGH CENTRAL ALABAMA AT 1200 UTC ONLY TO WEAKEN IT TO 999 MB AS IT MOVES NEAR ATLANTA...GEORGIA AT 1800 UTC. THE VERY HIGH RAINFALL RATES ACCOMPANYING A BRIEF DEEPENING OF THE SURFACE SYSTEM IS A COMMON SIGN OF CONVECTIVE FEEDBACK. THE GFS TAKES THE WINDS TO GALE FORCE THU MORNING DURING THE PEAK OF THE FEEDBACK. THE ECMWF HAS A MORE NW SOLUTION WITH THE LOW TRACK...BUT DOES NOT SUGGEST WINDS ABOVE 30 KT ANYWHERE NEAR THE SYSTEM. THEREFORE...HEDGED THE FORECAST TOWARD A WEAKER VERSION OF THE GFS ON THU. CARIBBEAN AND TROPICAL N ATLC W OF 55W... THE GALE WARNING ALONG THE COAST OF COLOMBIA WILL BE CANCELED THIS MORNING. THERE HAS NOT BEEN AN OBSERVATION OF GALE FORCE WINDS IN THIS REGION IN OVER 12 HOURS AND THE 0214 UTC ASCAT PASS SHOWS THE AREA OF STRONG TRADES SHRINKING AND WINDS ONLY TO 25 KT. THE DROP IN WIND SPEEDS HERE IS DUE TO THE PROGRESS OF THE FRONT OVER THE GULF WHICH HAS SHIFTED THE RIDGE AXIS EXTENDING FROM NORTHERN CUBA TO 1026 MB HIGH PRES NEAR 29N64W FARTHER E AND WEAKENED IT OVER THE CARIBBEAN. THIS HAS DECREASED THE GRADIENT BETWEEN THE RIDGE AND THE CLIMATOLOGICAL LOW PRES OVER COLOMBIA. THERE IS A DISSIPATING LOW LEVEL BOUNDARY FARTHER E THAT CONTINUES TO BRING WARM CLOUD TOP SHOWERS TO THE DOMINICAN REPUBLIC...PUERTO RICO...AND THE VIRGIN ISLANDS. EXPECT THE HIGH PRES TO THE N TO BE FORCED EASTWARD BY THE COLD FRONT PASSING FROM THE GULF INTO THE WESTERN ATLC TODAY. THIS WILL BRING THE TRADES DOWN A NOTCH TODAY ONLY TO REBUILD EARLY IN THE WEEK AS HIGH PRES BUILDS BEHIND THE COLD FRONT. THE WEAKENED FRONT WILL PASS THROUGH THE YUCATAN CHANNEL TODAY AND GET HUNG UP OVER THE WINDWARD CHANNEL MON AND TUE. WINDS WILL TURN MORE SOUTHEASTERLY IN THE NW CARIBBEAN BY WED AS THE AFOREMENTIONED SYSTEM PASSES THROUGH THE GULF COAST STATES. SW N ATLC S OF 31N W OF 55W... A GALE WARNING IS IN EFFECT OFF THE NE FL COAST DUE TO THE BUILDING PRES GRAD BETWEEN THE 1026 MB SURFACE HIGH NEAR 29N64W AND THE GULF LOW AND COLD FRONT. AS OF NOW...WINDS ARE GUSTING TO GALE FORCE...BUT THEY ARE EXPECTED TO PICK UP SLIGHTLY AS THE FRONT MOVES CLOSER TODAY. WITH THE UPPER PATTERN THEN MOVING TOWARD A MORE PROGRESSIVE/ZONAL SOLUTION...THE PREFERRED MODEL BECOMES THE GFS AS THE SYSTEM PUSHES E OF THE AREA THROUGH TUE. THE GFS AND ITS ENSEMBLES SHOW WINDS DROPPING BELOW GALE FORCE OVER FORECAST WATERS BY SUNSET...WITH THE GALE CONTINUING JUST NORTH OF THE AREA NEAR THE FRONT. HIGH PRES MOVES ACROSS THE AREA TUE AND WED. DIFFERENCES IN THE MODELS DISCUSSED IN THE GULF OF MEXICO SECTION BEGIN TO IMPACT THE NW PORTION OF THE AREA THU...WITH THE GFS INCREASING WINDS TO GALE FORCE AHEAD OF THE NEXT LOW PRES SYSTEM PASSING THROUGH THE SOUTHEAST. THE MORE NW ECMWF KEEPS WINDS TO 30 KT. WHILE THE FASTER GFS TIMING IS PREFERRED WITH THE LOW CENTER...BELIEVE IT IS TOO STRONG DUE TO FEEDBACK. WILL NOT MENTION GALES POSSIBLE IN THE OFFSHORES JUST YET. WARNINGS... ATLC... .GALE WARNING S OF 25N BETWEEN 80W AND 82W TODAY...AMZ080. .GALE WARNING N OF 29N W OF 74W TODAY...AMZ080. CARIBBEAN... .NONE. GULF OF MEXICO... .GALE WARNING S OF 25N BETWEEN 80W AND 82W TODAY...GMZ086. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER SCHAUER