000 AGXX40 KNHC 291950 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 250 PM EST TUE DEC 29 2015 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: BLEND OF GFS/NWPS WITH PREVIOUS FORECAST. HIGH CONFIDENCE. AT 12 UTC...A STATIONARY FRONT REACHED FROM NEAR PANAMA CITY TO NEAR CIUDAD DEL CARMEN IN THE SW GULF OF MEXICO. THE RIDGE OVER THE WESTERN ATLC IS STARTING TO BUILD WESTWARD...ALLOWING THE FRONT TO START TO MOVE WESTWARD AS A WARM FRONT. THE FRONT WILL REACH FROM THE MOUTH OF MISSISSIPPI RIVER TO THE FAR SW GULF BY EARLY EARLY WED. GLOBAL MODELS INDICATED A STRONG MID/UPPER TROUGH MOVING THROUGH THE OHIO VALLEY BY MIDWEEK...ALLOWING THE NORTHERN PORTION OF THE FRONT TO CROSS THE NORTHERN WATERS THROUGH FRI. THE FRONT WILL EVENTUALLY EXTEND FROM SW FLORIDA TO SW GULF BY LATE SAT. THE MAIN FORECAST ISSUE WILL BE THE POSSIBILITY OF GALES OFF THE COASTLINES OF TAMAULIPAS AND VERACRUZ FRI INTO SAT BEHIND THE FRONT AS HIGH PRES AND COOLER DRIER AIR MOVE INTO THE REGION. GLOBAL MODELS ARE IN GOOD AGREEMENT WITH EACH OTHER AND WITH SREF OUTPUT REGARDING THE POSSIBILITY OF GALES. WINDS AND SEAS DIMINISH STARTING SUNDAY FROM WEST TO EAST ACROSS THE BASIN. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: BLEND OF GFS/NWPS GUIDANCE WITH PREVIOUS FORECAST. MEDIUM CONFIDENCE. RIDGING NORTH OF THE AREA IS MAINTAINING STRONG TO NEAR GALE FORCE WINDS ACROSS MAINLY THE CENTRAL CARIBBEAN. A 15 UTC ASCAT PASS INDICATED NEAR GALE FORCE WINDS OFF THE COAST OF COLOMBIA...IN LINE WITH ASSUMPTIONS THAT THE GALE CONDITIONS PREVIOUSLY IN PLACE WOULD HAVE DIMINISHED SLIGHTLY BY MID MORNING. THIS LULL WILL BE TEMPORARY HOWEVER AS WINDS WILL INCREASE AGAIN THIS EVENING DUE TO OVERNIGHT ENHANCEMENT ALONG THE MOUNTAINOUS COASTLINE. THE GALES WILL DIMINISH SLIGHTLY TOMORROW BY LATE MORNING...BUT INCREASE AGAIN WED NIGHT AND POSSIBLY THU NIGHT. THE RIDGE WILL WEAKEN AND SHIFT EAST FRI AHEAD OF AN ADVANCING COLD FRONT...ALLOWING THE TRADE WINDS TO DIMINISH SLIGHTLY THROUGH THE WEEKEND. SHIP OBSERVATIONS AND THE 15 UTC ASCAT PASS INDICATED SE WINDS TO AT LEAST 20 KT OVER THE FAR NW CARIBBEAN AS WELL. WINDS TO 25 KT ARE LIKELY THROUGH THE BAY ISLANDS AND GULF OF HONDURAS OVERNIGHT THROUGH THU NIGHT. FARTHER EAST...EAST SWELL WITH SEAS 8 TO 9 FT IS PROPAGATING INTO THE TROPICAL N ATLC WATERS EAST OF THE WINDWARD ISLANDS...AND WILL EXPAND NORTHWARD TO COVER THE WATERS OFF THE LEEWARD ISLANDS BY EARLY WED...AND PERSIST THROUGH LATE SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: BLEND OF GFS/NWPS GUIDANCE WITH PREVIOUS FORECAST. HIGH CONFIDENCE THROUGH SAT THEN MEDIUM CONFIDENCE. THE SUBTROPICAL RIDGE REMAINS IN PLACE ALONG ROUGHLY 30N SUPPORTING PULSES OF STRONG TRADE WIND FLOW OFF THE COAST OF HISPANIOLA AND INTO THE TCI AND SOUTHERN BAHAMAS. MODERATE SE WINDS ARE NOTED ELSEWHERE. LITTLE CHANGE IS ANTICIPATED INTO FRI...WHEN A COLD FRONT EMERGES OFF THE NE FLORIDA COAST. THE FRONT WILL REACH FROM BERMUDA TO SE FLORIDA BY LATE SAT THEN STALL. THE PAST SEVERAL GFS RUNS HAVE BEEN SHOWING AN ACTIVE SOUTHERN STREAM FORMULATING A WEAK SURFACE LOW ALONG THE FRONTAL BOUNDARY STARTING SAT. THE 12Z ECMWF IS COMING MORE IN LINE WITH THIS SCENARIO AS WELL...AND THE LATEST OFFICIAL FORECAST FAVORS A BLEND WITH THE ECMWF FOR SUN AND MON. THE GFS REMAINS MORE AGGRESSIVE WITH GALES POSSIBLE BY EARLY SUN NORTH OF GRAND BAHAMA. THE ECMWF IS FASTER BUT WEAKER...BUT ALSO SHOW BRIEF GALES NE OF THE CENTRAL BAHAMAS. GIVEN THE UNCERTAINTY ON TIMING AND LOCATION...WINDS AND SEAS ARE A LITTLE BELOW GUIDANCE CURRENTLY BUT MAY HAVE TO BE INCREASED IF TRENDS PERSIST IN LATER RUNS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... .GMZ017...W CENTRAL GULF FROM 22N TO 26N W OF 94W... GALE CONDITIONS POSSIBLE FRI NIGHT. .GMZ023...SW GULF S OF 22N W OF 94W... GALE CONDITIONS POSSIBLE FRI NIGHT INTO SAT. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W INCLUDING COLOMBIA BASIN... GALE WARNING TONIGHT INTO THU. GALE CONDITIONS POSSIBLE THU NIGHT. .AMZ033...CARIBBEAN S OF 15N BETWEEN 64W AND 72W INCLUDING VENEZUELA BASIN... GALE WARNING TONIGHT. GALE WARNING WED NIGHT. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 CHRISTENSEN. NATIONAL HURRICANE CENTER.