000 AGXX40 KNHC 301824 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 124 PM EST SUN NOV 30 2014 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: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST THROUGH WED THEN ECMWF ADDED INCREASINGLY TO THE BLEND THROUGH FRI. LATEST TAFB-NWPS USED TO ADJUST WAVE PARAMETERS. HIGH CONFIDENCE. FRESH TO STRONG TRADE WINDS ARE IN PLACE S OF 25N E OF 85W... INCLUDING THE STRAITS OF FLORIDA...TO THE S OF A RIDGE STRETCHED OVER THE NORTHERN GULF OF MEXICO. FRESH TO STRONG TRADES ARE FORECAST TO CONTINUE THROUGH EARLY TUE MORNING WHEN THE RIDGE IS FORECAST TO SHIFT EASTWARD. THIS WILL ALLOW A COLD FRONT TO MOVE INTO THE FAR NW WATERS BY MON NIGHT. THE FRONT WILL STALL OVER THE NORTHERN WATERS BY TUE AND QUICKLY RETREAT INLAND WED AS HIGH PRESSURE BUILDS BACK ACROSS THE GULF WATERS. A BLEND OF THE GFS AND ECMWF WAS USED TO ADJUST THE FORECAST WED ONWARD THE AMPLIFICATION OF HIGH PRES OVER THE GULF WILL BE IMPACTED BY THE STRENGTH AND POSITION OF A SURFACE LOW EXPECTED TO DEVELOP IN THE CENTRAL ATLC NEAR 25N-30N FRI. HOWEVER...ONCE THE FRESH TO STRONG TRADES IN THE SE GULF DIMINISH MON...WINDS AND SEAS WILL REMAIN BELOW ADVISORY CRITERIA OVER THE FORECAST WATERS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST THROUGH WED THEN ECMWF ADDED INCREASINGLY TO THE BLEND THROUGH FRI. LATEST TAFB-NWPS USED TO ADJUST WAVE PARAMETERS. HIGH CONFIDENCE THROUGH WED THEN MEDIUM CONFIDENCE. THE 1412 UTC AND 1552 UTC ASCAT-B PASSES SHOW A SIZABLE AREA OF FRESH TO STRONG WINDS BETWEEN CUBA AND THE SHEAR LINE STRETCHED FROM THE WINDWARD PASSAGE TO EASTERN HONDURAS...WITH FRESH TO STRONG WINDS ALSO NOTED IN THE WESTERN WINDWARD PASSAGE AND WINDS TO NEAR GALE FORCE REPORTED OFF THE COAST OF COLOMBIA. IN GENERAL...THE GFS DID A GOOD JOB INITIALIZING THESE STRONG WINDS. IT IS ABOUT 5 KT TOO WEAK IN THE WINDWARD PASSAGE...A BIAS FREQUENTLY NOTED IN NE FLOW. THE WINDS AND SEAS WILL INCREASED MANUALLY DURING THE PERIOD OF NE WINDS IN THE PASSAGE BECAUSE OF THIS. THE SHEAR LINE SHOULD DISSIPATE TONIGHT. WITH STRONG HIGH PRESSURE CENTERED N OF THE AREA...A TIGHT PRESSURE GRADIENT WILL PREVAIL OVER THE CENTRAL CARIBBEAN AND PRODUCE FRESH TO STRONG WINDS OVER MUCH OF THE AREA THROUGH TUE MORNING. HIGH PRESSURE WILL WEAKEN MIDWEEK WHICH WILL LOOSEN THE GRADIENT AND DECREASE THE TRADES OVER THE CARIBBEAN WATERS. CONFIDENCE IN THE FORECAST WANES BY WED-FRI WHEN THE GFS BECOMES A MORE AMPLIFIED AND WESTERLY SOLUTION WITH THE INVERTED TROUGH AND POSSIBLE LOW PRES SYSTEM DEVELOPING IN THE CENTRAL ATLC NEAR 25-30N ON FRI COMPARED TO THE OTHER GLOBAL MODELS. THE GFS ALSO BECOMES AN OUTLIER BY DEVELOPING A SECOND AREA OF LOW PRES OVER THE S CENTRAL CARIBBEAN THU ALONG THE TROUGH CONNECTED TO THE AFOREMENTIONED LOW PRES SYSTEM TO THE NE. THE ECMWF LOOKS MORE REASONABLE HERE...SO IT WAS WEIGHTED MORE HEAVILY WITH TIME. IN THE TROPICAL N ATLC...WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA THROUGH THE FORECAST PERIOD. ...SW N ATLANTIC S OF 31N W OF 55W INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST THROUGH WED THEN ECMWF ADDED INCREASINGLY TO THE BLEND THROUGH FRI. LATEST TAFB-NWPS USED TO ADJUST WAVE PARAMETERS. HIGH CONFIDENCE. HIGH PRESSURE N OF THE AREA IS DRIVING FRESH TO STRONG NE TRADE WINDS SEEN BY THE 1410 UTC ASCAT-B AND 1458 UTC ASCAT-A PASSES ACROSS AND N OF THE SE BAHAMAS. TRADES WILL BEGIN TO DIMINISH TUE AS THE AREA OF HIGH PRESSURE SHIFTS NE OF THE AREA AND A BROAD TROUGH APPROACHED THE AREA FROM THE EAST. THE GFS BECOMES A MORE AMPLIFIED AND WESTERLY SOLUTION WITH THIS INVERTED TROUGH AND A POSSIBLE LOW PRES SYSTEM DEVELOPING IN THE CENTRAL ATLC NEAR 25-30N ON FRI COMPARED TO THE OTHER GLOBAL MODELS. THE ECMWF LOOKS MORE REASONABLE HERE...SO IT WAS WEIGHTED MORE HEAVILY WITH TIME. BOTH MODELS INCREASE WINDS OVER NE WATERS FRI AS THE LOW DEVELOPS...BUT THE ECMWF IS LESS AGGRESSIVE. THE ECMWF WAVE MODEL AND NWPS WERE USED TO ADJUST THE SEAS. BOTH MODELS ARE LOWER WITH WAVE HEIGHTS THAN THE MWW3 OVER NE WATERS THU AND FRI. THE LARGER SEAS IN THE NWPS ALSO APPEAR TO BE BETTER INITIALLY ACROSS THE EASTERN BAHAMAS IN NE SWELL COMPARED TO THE MWW3. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.