000 AGXX40 KNHC 220719 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 320 AM EDT SAT SEP 22 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... A LIGHT TO GENTLE EASTERLY BREEZE DOMINATES MUCH OF THE GULF THIS MORNING. A TROPICAL WAVE PASSING THROUGH YUCATAN WILL MOVE W THROUGH THE GULF S OF 23N THROUGH LATE MON. THE TROPICAL WAVE WILL PRIMARILY BE A FOCUS FOR CONVECTION. WINDS AND SEAS ARE NOT EXPECTED TO MEET ADVISORY CRITERIA. A WEAK COLD FRONT WILL MOVE THROUGH THE NORTHERN GULF ON SUN AND LINGER OVER THE CENTRAL GULF INTO TUE BEFORE GRADUALLY DISSIPATING THROUGH WED. THE BUILDING PRES GRADIENT BETWEEN HIGH PRES BEHIND THE COLD FRONT AND LOWER PRES OVER THE SW GULF NEAR THE TROPICAL WAVE WILL INCREASE WINDS TO A FRESH BREEZE AND SEAS TO 4-6 FT PRIMARILY OVER THE CENTRAL GULF MON BEFORE THE GRADIENT RELAXES. THE MODELS ARE IN REASONABLE AGREEMENT ON THE TIMING AND STRENGTH OF THIS FRONT OVER THE GULF AS WELL AS THE OTHER FEATURES. A BLEND OF THE 00Z GFS AND ECMWF WILL BE USED TO ADJUST THE FORECAST. SOUTHWEST NORTH ATLC S OF 31N W OF 55W... A SURFACE TROUGH IS EXPECTED TO LINGER BETWEEN SOUTHEAST FLORIDA AND THE BAHAMAS TODAY INTO SUN BEFORE MERGING WITH THE COLD FRONT MOVING SOUTHWARD ALONG THE E COAST OF FLORIDA BY MON. THIS TROUGH WILL BE A FOCUS FOR CONVECTION. THE 00Z GFS CARRIES A STRONGER MID LEVEL VORT ASSOCIATED WITH THE SURFACE TROUGH NORTHEASTWARD INTO THE LEADING EDGE OF THE DEEP LAYER TROUGH SUPPORTING THE COLD FRONT ON SUN COMPARED TO THE OTHER MODELS. AS A RESULT...THE GFS CARRIES A SURFACE WAVE ALONG THE FRONT BY SUN THAT QUICKLY MOVES NE OF THE AREA. INSTEAD OF CARRYING THIS ENERGY NORTHEASTWARD...THE UKMET STALLS THE FRONT AND SPLITS THE MID LEVEL ENERGY...WITH A PORTION HEADING NE AND THE REST RETROGRADING BACK INTO FLORIDA BY WED. THE 00Z ECMWF SIMPLY MERGES THE ENERGY WITH THE BOUNDARY AND EXPELS IT NORTHEASTWARD WITH NO SIGNIFICANT SURFACE WAVE DEVELOPMENT OVER THE FORECAST AREA. WITH SOME UNCERTAINTY NOTED AMONG THE MODELS...PREFER TO LEAN TOWARD A WEAKER VERSION OF THE 00Z GFS WHICH SLOWS THE FRONT DOWN MORE THAN THE ECMWF BY SUN AS THE TROUGH MERGES WITH IT...BUT DOES NOT HOLD UP THE FRONT AS MUCH AS THE UKMET. CARIBBEAN SEA AND TROPICAL N ATLC W OF 55W... GENTLE TO MODERATE TRADE WINDS PREVAIL ACROSS THE CARIBBEAN WATERS AND THE TROPICAL N ATLC WATERS...EXCEPT FOR FRESH TO STRONG NE-E WINDS IN THE S CENTRAL CARIBBEAN WATERS WHERE SEAS ARE UP TO 8 FT. SHIP DDSB2 CONFIRMED THESE CONDITIONS AT 0000 UTC WHEN IT REPORTED 25 KT WINDS NEAR 12.5N74W. A FRESH TO STRONG BREEZE IS FORECAST TO CONTINUE HERE THROUGH MON MORNING...WITH HIGH PRES OVER THE SE UNITED STATES BEHIND THE COLD FRONT IN THE GULF BEGINNING TO BREAK DOWN BY THAT TIME...WEAKENING THE PRES GRADIENT OVER THE CENTRAL CARIBBEAN. THE TROPICAL WAVE NEAR 45W IS FORECAST TO PUSH THROUGH THE TROPICAL N ATLC SUN AND MON...PASSING THROUGH THE CENTRAL CARIBBEAN BY WED WITH LITTLE FANFARE. CURRENTLY...BUOY 41041 IS REPORTING 8 FT SEAS AND 17 KT NE WINDS JUST AHEAD OF THE WAVE. HOWEVER...THE RIDGE TO THE N THAT EXTENDS BETWEEN THE REMNANT LOW OF NADINE AND THE PERSISTENT LOW PRES SYSTEM E OF BERMUDA IS FORECAST TO WEAKEN...DIMINISHING THE PRES GRADIENT AND THE WIND FIELD NEAR THE WAVE. THIS WAVE SHOULD CARRY CONDITIONS THAT ARE JUST BELOW ADVISORY CRITERIA THROUGH THE WEEKEND AND WEAKEN FURTHER AS IT APPROACHES THE LESSER ANTILLES. THE WEAK TROPICAL WAVE THAT WAS ANALYZED OVER THE MONA PASSAGE AT 0000 UTC HAS BECOME DIFFICULT TO FOLLOW OVER THE CARIBBEAN AS IT MOVES THROUGH A MID LEVEL DEFORMATION ZONE. THERE IS NO SIGNIFICANT SIGNAL THAT THE WAVE IS STILL IN PLACE AND IT WAS DROPPED FROM THE SURFACE ANALYSIS. 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