000 AGXX40 KNHC 311733 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1233 PM EST SAT JAN 31 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: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST WHICH WAS A GFS/ECMWF BLEND. TAFB NWPS USED FOR WAVE HEIGHTS. MED CONFIDENCE. THE COLD SEGMENT OF A FRONT E OF 87W WILL CONTINUE A LITTLE FURTHER S TODAY BEFORE STALLING AND TRANSITIONING A WARM FRONT TONIGHT. THE FRONTAL SEGMENT W OF 87W HAS ALREADY TRANSITIONED TO A NORTHWARD MOVING WARM FRONT. STILL EXPECT THE WARM FRONT TO SET OFF A FEW TSTMS AS THE IT PASSES ACROSS THE FL PANHANDLE ON SUN AND THIS IS REFLECTED IN THE WEATHER GRIDS. EXPECT NE-E 15- 20 KT FLOW N OF THE COLD FRONT TODAY THEN RAPIDLY CLOCKING TO THE E-SE AT 20-25 KT ACROSS THE E GULF TONIGHT AND SUN ALL TO THE NE OF THE WARM FRONT. MODERATE RETURN FLOW EXPECTED ACROSS THE CENTRAL AND W GULF SW OF THE WARM FRONT AND AHEAD OF THE NEXT COLD FRONT ARRIVING OVER THE NW GULF ON SUN EVENING...AND THEN RACING SE THROUGH THE FL STRAITS ON MON EVENING WHILE LEAVING THE FAMILIAR NE-SE ORIENTATED FRONTAL TROUGH REMNANTS OVER THE SW GULF WATERS ON MON NIGHT AND TUE. THIS REMNANT TROUGH IS EXPECTED TO LIFT N ON TUE NIGHT...WITH GUIDANCE NOW HINTING AT A LOW PRES DEVELOPMENT FURTHER N NEAR THE TX COASTAL BEND AROUND SUNRISE ON WED. NOTING THAT THE ASSOCIATED UPPER FEATURE THAT WILL BE RESPONSIBLE FOR THIS SCENARIO IS CURRENTLY SHIFTING SE ACROSS SOUTHERN CALIFORNIA SO LIKELY SEE MORE ADJUSTMENTS IN THE GUIDANCE. THE OFFICIAL GRIDS WILL USE A GFS/ECMWF BLEND WHICH TRACKS THE LOW E ALONG 28N ACROSS THE N- CENTRAL GULF ON WED NIGHT AND INLAND FL NEAR TAMPA BAY ON THU EVENING. EXPECT SW 15 KT CONDITIONS AHEAD OF THIS SECOND FRONT ON MON AND N-NE 20-30 KT FLOW BEHIND THE FRONT BY SUNRISE MON...BUT QUICKLY DIMINISHING TO NE 10-15 KT MON NIGHT. SE RETURN FLOW WILL SET UP ACROSS THE WESTERN GULF TO THE E OF THE REMNANT TROUGH ON TUE NIGHT INCREASING TO 20-25 KT E OF THE DEVELOPING LOW BRIEFLY ON WED. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST WHICH WAS A GFS/ECMWF. TAFB NWPS USED FOR WAVE HEIGHTS. MED-HIGH CONFIDENCE. WEAK REMNANTS OF FRONTAL TROUGH STILL EVIDENT ACROSS HISPANIOLA AND THE NW CARIBBEAN WITH OVERCAST LOW/MID DECK AND EMBEDDED SHOWERS WHICH ARE DENOTED IN WEATHER GRIDS. THE LOW LEVEL FLOW IS NE 15-20 KT ACROSS THE NW CARIBBEAN AND STILL EXPECT SOME REINFORCING TONIGHT BEHIND A RAPIDLY MOVING COLD FRONT THAT WILL BRUSH THE NW CARIBBEAN RESULTING IN PATCHES OF 20-25 KT WINDS AND SEAS OF 6-9 FT MAINLY IN WINDWARD PASSAGE THIS AFTERNOON AND DEVELOPING BETWEEN CUBA AND THE CAYMANS TONIGHT. THE GRADIENT SHOULD RELAX ON SUN AFTERNOON AS THE FLOW CLOCKS TO THE E-SE 10- 15 KT ON SUN NIGHT AND 5-10 KT ON MON AHEAD OF A WEAK COLD FRONT ARRIVING AT THE YUCATAN CHANNEL ON MON EVENING...WITH N-NE 10-15 KT CONDITIONS EXPECTED N OF THE DISSIPATING FRONT ON MON NIGHT INTO TUE...INCREASING TO NE-E 15-20 KT ON TUE NIGHT AND WED... THEN RELAXING TO SE 10-15 KT WED NIGHT AND THU. NE-E 20-30 KT WINDS WITH 8-11 FT SEAS EXPECTED WITHIN 240 NM OF THE NW COAST OF COLOMBIA THIS AFTERNOON INTO THIS EVENING. THE GRADIENT WILL TIGHTEN LATER TONIGHT INCREASING THE NE FLOW TO 30- 35 KT/SEAS 10-13 FT WITHIN ABOUT 120 NM OF THE COAST. EXPECT THIS NOCTURNAL GALE PATTERN TO CONTINUE EACH NIGHT THROUGH THU NIGHT. THE EXTENT OF NEAR GALE AND MINIMAL GALE WINDS WILL EXPAND OUT TO 180 NM FROM THE COAST OF COLOMBIA ON SUN THROUGH WED NIGHTS WITH SEAS BUILDING TO AS HIGH AS 16 KT. NE-E 15-20 KT TRADES EXPECTED ELSEWHERE ACROSS CARIBBEAN BETWEEN 67-85W AND EASTERLY 10-15 KT FLOW ACROSS THE EASTERN CARIBBEAN AND TROPICAL ATLC WATERS THROUGH SUN...WITH THE TIGHTENING GRADIENT SUPPORTING 15-20 KT CONDITIONS SUN NIGHT THROUGH EARLY WED. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST WHICH GFS/ECMWF BLEND. TAFB NWPS USED FOR WAVE HEIGHTS. MED-HIGH CONFIDENCE. A 150 NM WIDE COLD FRONT EXTENDING FROM 31N60W TO ACROSS ANDROS ISLAND TO THE FL STRAITS WILL RACE E AND MERGE WITH REMNANTS OF ANOTHER FRONT CURRENTLY OVER THE TROPICAL WATERS NE OF THE LEEWARDS LATE SAT NIGHT WITH THE MERGED BOUNDARY EXTENDING FROM 26N55W TO THE LEEWARDS WITH THE FRONT LOSING IDENTITY BY MON. SOUTHWESTERLY 20-25 KT WINDS WILL CONTINUE N OF 28N WITHIN 240 NM E OF THE FRONT TILL IT PASSES 55W. A LARGE AREA OF POST- FRONTAL 20-30 KT CURRENTLY OBSERVED N OF 27N WITHIN 690 NM W OF THE FRONT ARE EXPECTED TO INCREASE TO MINIMAL GALE 30-35 KT CONDITIONS TONIGHT N OF 30N WITHIN 600 NM W OF THE FRONT...AND CONTINUE THROUGH SUN AFTERNOON AS THE STRONGEST WINDS SHIFT E OF 65W. A POST-FRONTAL SURFACE HIGH WILL SHIFT SE INTO THE AREA NEAR 30N72W ON SUN AFTERNOON WITH A RIDGE EXTENDING W TO PORT CANAVERAL. SOUTHERLY FLOW N OF THE RIDGE WILL INCREASE TO 20-25 KT ON SUN EVENING...AND FURTHER INCREASE TO A 30-35 KT MINIMAL GALE N OF 30N W OF 77W LATE SUN NIGHT...AND CONTINUE ON MON AHEAD OF ANOTHER COLD FRONT...WITH NW 30-35 KT MINIMAL GALE CONDITIONS DEVELOPING N OF 30N WITHIN 180 NM W OF THE FRONT ON MON AFTERNOON. OTHERWISE A SW-W-NW 20-30 KT WIND SHIFT EXPECTED N OF 28N ALONG THE FRONT AS IT PASSES ACROSS THE AREA ON TUE- WED. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W INCLUDING COLOMBIA BASIN... GALE WARNING TONIGHT. GALE WARNING SUN NIGHT. GALE CONDITIONS POSSIBLE MON NIGHT. GALE CONDITIONS POSSIBLE TUE NIGHT. GALE CONDITIONS POSSIBLE WED NIGHT. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ111...ATLANTIC FROM 27N TO 31N W OF 77W... GALE WARNING MON. GALE CONDITIONS POSSIBLE MON. .AMZ113...ATLANTIC FROM 27N TO 31N BETWEEN 70W AND 77W... GALE CONDITIONS POSSIBLE MON INTO MON NIGHT. $$ *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 NELSON. NATIONAL HURRICANE CENTER.