000 AGXX40 KNHC 120647 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 247 AM EDT TUE APR 12 2016 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS. ...GULF OF MEXICO... MODEL PREFERENCE: 0Z GFS BLENDED WITH THE OFFICIAL WIND FORECAST. THE 00Z NWPS BLENDED WITH THE OFFICIAL WAVE FORECAST. MEDIUM CONFIDENCE. THE MODELS AGREE ON WINDS REMAINING BELOW A FRESH TO STRONG BREEZE WITH THE WEAK COLD FRONT ENTERING THE NW GULF TODAY AND SETTLING IN THE N GULF N OF 27N WED AND THU. ELSEWHERE...THE 00Z GFS SHOWS A FRESH TO OCCASIONALLY STRONG BREEZE INITIATING ALONG THE NW COAST OF THE YUCATAN PENINSULA IN THE EVENING AND DISSIPATING AS IT MOVES W WITH THE THERMAL TROUGH OVERNIGHT. THE GFS GENERALLY HANDLES THIS BETTER THAN THE OTHER MODELS...SO THE GFS IS PREFERRED THROUGH THU. BY THU NIGHT...THE COLD FRONT STRETCHED ACROSS THE N GULF BEGINS TO MOVE S THROUGH THE E GULF. THE 00Z GFS AND UKMET AGREE ON INCREASING WINDS TO A FRESH TO STRONG BREEZE IN THE NE GULF BEHIND THE FRONT WHILE THE 12Z/11 ECMWF IS WEAKER. THESE DIFFERENCES STEM FROM THE HANDLING OF SHORTWAVE ENERGY OVER THE TENNESSEE VALLEY THU NIGHT AND FRI. THE ECMWF IS WEAKER WITH THIS ENERGY AND SLOWER TO PHASE IT INTO THE TROUGHING IN THE W ATLC THAN THE OTHER MODELS OR ENS MEANS. THE ECMWF IS AN OUTLIER. THE GFS AND UKMET BECOME MORE AMPLIFIED WITH THE H5 PATTERN AND DEVELOP A BROAD AREA OF FRESH TO STRONG EASTERLY FLOW ACROSS THE N GULF OVERNIGHT FRI NIGHT. THE GFS SOLUTION IS PREFERRED FOR ADJUSTING THE GRIDS. THE 00Z NWPS INCORPORATED THIS PREFERRED WIND FORECAST AND WILL BE USED TO ADJUST THE WAVE GRIDS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 00Z GFS BLENDED WITH THE OFFICIAL WIND FORECAST. THE 00Z NWPS BLENDED WITH THE OFFICIAL WAVE FORECAST. HIGH CONFIDENCE. THE MODELS GENERALLY COMPARED WELL TO THE 0254Z ASCAT-B PASS FOR THE AREAS OF 25 KT WINDS OFF COLOMBIA AND IN THE LEE OF CUBA. THE 00Z GFS GENERALLY DOES BETTER OFF OF COLOMBIA WITH THE TERRAIN INFLUENCED WIND ENHANCEMENT. IT WAS PREFERRED EARLY IN THE PERIOD AS WELL AS LATER IN THE PERIOD WHEN A FRESH TO STRONG BREEZE IS EXPECTED TO PULSE ONCE AGAIN ALONG THE COAST OF COLOMBIA THU NIGHT THROUGH SAT NIGHT. AS STATED ABOVE...THE 00Z GFS AND 00Z UKMET ARE FAVORED OVER THE 12Z/11 ECMWF WITH THE GENERAL PATTERN N OF THE AREA...ESPECIALLY BY THU NIGHT. THE MORE AMPLIFIED PATTERN OF THE GFS SHOULD ALLOW A FRESH BREEZE TO DEVELOP ALONG THE N COAST OF HONDURAS FRI NIGHT AND INCREASE TO FRESH TO STRONG SAT NIGHT AS HIGH PRES BUILDS TO THE N...INCREASING THE PRES GRADIENT HERE. IN THE TROPICAL ATLC...THE PREFERENCE FOR WIND HAS BEEN HEDGED TOWARD THE 00Z GFS. SEE THE SW N ATLC SECTION BELOW FOR DETAILS CONCERNING THE TROUGHING N OF THE NE CARIBBEAN. THIS TROUGHING WILL WEAKEN THE WINDS ACROSS THE TROPICAL ATLC. ANY SIGNIFICANT SWELL IS EXPECTED TO WANE EARLY IN THE PERIOD. THE 00Z NWPS...MWW3 AND EC WAVE ALL COMPARE WELL TO THE 2150Z ALTIMETER PASS THAT STRETCHED THROUGH THE TROPICAL N ATLC ZONES. THE 00Z NWPS SEEMS REASONABLE FOR ADJUSTING THE SEAS UNTIL LATE THU WHEN IT APPEARS TO ARTIFICIALLY BUMP UP SEAS A BIT MORE THAN THE OTHER MODELS. WILL HEDGE MORE TOWARD THE OFFICIAL FORECAST LATE IN THE PERIOD FOR SEAS HERE AS A RESULT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: 12Z/11 ECMWF BLENDED WITH THE OFFICIAL WIND FORECAST UNTIL WED NIGHT THEN THE 00Z GFS BLENDED WITH OFFICIAL. THE 12Z/11 EC WAVE BLENDED WITH THE OFFICIAL WAVE FORECAST UNTIL WED NIGHT THEN 00Z MWW3 BLENDED WITH OFFICIAL. MEDIUM CONFIDENCE. THE HIGHER SEAS SEEN IN THE 12Z/11 EC WAVE ARE MATCHING UP BETTER TO THE ALTIMETER PASS EXTENDING THROUGH 31N70W AT 2304Z THAN THE 00Z MWW3 OR 00Z NWPS. THE 12Z/11 ECMWF IS ALSO A BETTER MATCH FOR THE 0118Z ASCAT-B PASS IN NE WATERS N OF THE STATIONARY FRONT. THE ECMWF IS PREFERRED AS THIS FRONT WEAKENS AND DISSIPATES THROUGH WED NIGHT. BEGINNING THU...THE 12Z/11 ECMWF STRAYS FROM THE MODEL CONSENSUS BY CARRYING A LESS AMPLIFIED PATTERN FROM THE WESTERN ATLC THROUGH THE MISSISSIPPI VALLEY THAN THE MODEL CONSENSUS. THE 00Z GFS AND UKMET ARE IN AGREEMENT ON DEVELOPING A COASTAL BOUNDARY OFF THE SOUTHEASTERN COAST...PRIMARILY N OF THE AREA...THAT WILL FUNNEL FRESH TO STRONG NE WINDS IN THE COASTAL ZONES WHILE THE ECMWF CARRIES MUCH WEAKER FLOW. THE UKMET AND GFS ALSO AGREE ON CARRYING A LOW PRES SYSTEM FARTHER S OFF THE N FL COAST THAN THE ECMWF THU. IN ADDITION...THEY CARRY STRONGER TROUGHING N OF THE NE CARIBBEAN AND BOTH DEVELOP A DISTINCT SURFACE LOW BY EARLY THU THAT WILL DRIFT N-NE. THE UKMET AND GFS SOLUTIONS ARE SUPPORTED BY THE GEFS MEAN AS WELL AS THE EC ENS MEAN WHICH IS MORE AMPLIFIED THAN THE DETERMINISTIC 12Z/11 ECMWF. THE GFS WAS USED TO ADJUST THE GRIDS. THE MWW3 WAS USED TO ADJUST THE WAVE GRIDS AFTER WED NIGHT AS TO MATCH THE WIND PREFERENCE. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER SCHAUER. NATIONAL HURRICANE CENTER.