000 AGXX40 KNHC 280650 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 250 AM EDT FRI MAR 28 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 WHICH IS A GFS/ECMWF BLEND. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST. MEDIUM-HIGH CONFIDENCE. A RIDGE EXTENDS FROM CEDAR KEY FL TO THE TX COASTAL BEND. SLY FLOW N OF THE RIDGE IS AT 20-25 KT/SEAS 6-10 FT WITH THE ELEVATED PLATFORMS REPORTING 25-35 KT. EXTENSIVE CLOUDINESS CONTINUES OVER THE NE WATERS...BUT LACKS SIGNIFICANT CONVECTION PER THE COASTAL RADARS...BUT I POPULATED THE NE ZONE WITH ISOL RW FOR TODAY WITH ISOL TS AS WELL STARTING TONIGHT. SCT RW/ISOL TS EXTENDS S OVER THE NW AND N CENTRAL COASTAL WATERS AND IS REFLECTED IN THE GRIDS. DENSE FOG DEVELOPING THE GRADIENT IS TIGHTENING ACROSS THE S-CENTRAL WATERS AND EXPECT AN INCREASE TO 20-25 KT SOON AND CONTINUING TODAY WITH THE GRADIENT RELAXING TONIGHT TO 15-20 KT AGAIN AS A COLD FRONT ENTERS THE NW WATERS. THE FRONT WILL BE ACCOMPANIED INITIALLY BY ONLY A SW-W-NW 5-10 KT WIND SHIFT...BUT INCREASING TO 15-20 KT TONIGHT WITH PATCHES OF 20-25 KT LATE SAT AS THE FRONT REACHES FROM THE FL BIG BEND TO THE YUCATAN PENINSULA. THE GRADIENT FURTHER TIGHTENS ON SAT EVENING INCREASING THE NLY FLOW TO 20-25 KT N OF THE FRONT MAINLY OVER THE NE GULF WATERS. THE FRONT WILL MOVE SE OF THE THE AREA ON SUN AFTERNOON. A SURFACE HIGH WILL SHIFT ACROSS THE SE CONUS WITH A RIDGE FROM THE MS DELTA TO THE NW BAY OF CAMPECHE ON SUN NIGHT...SHIFTING E AND BECOMING ORIENTATED FROM THE FL BIG BEND TO THE NE TX COAST ON MON NIGHT WITH SLY RETURN FLOW AT 10-15 KT S OF THE RIDGE THROUGH TUE. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 65W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST WHICH IS A GFS/ECMWF BLEND. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST. MEDIUM-HIGH CONFIDENCE. BKN TO LOCALLY OVC LOW-MID CLOUDS WITH EMBEDDED RW AND ONLY A FEW TSTMS...PER LIGHTNING DATA...DEFINE A 90 NM WIDE FRONTAL TROUGH OR SHEAR LINE EXTENDING FROM THE NE COAST OF HISPANIOLA WSW ACROSS NORTHERN HAITI AND JAMAICA...THEN TURNS WNW TO ACROSS GRAND CAYMAN TO 20N85W WHERE IT LOSES IDENTITY. SHIP REPORTS SUGGEST ONLY 10-15 KT NE-E SURFACE WINDS N OF THIS BOUNDARY TO THE W OF JAMAICA WITH A RECENT ALTIMETER PASS INDICATING 4-6 FT SEAS AND SUPPORTING 10-15 KT. THE LATEST ASCAT B PASS AT 02 UTC HAS NE-E 20-30 KT N OF THE FRONT E OF JAMAICA AND THROUGHOUT THE WINDWARD PASSAGE THUS MANUALLY ADJUSTMENTS MADE TO THE GRIDS. THE LATEST ASCATB CONFIRMS THE GALE WARNING WITHIN 60 NM OF THE COLOMBIAN COAST AT 11N74W. THE 2330 UTC ALTIMETER PASS RECORDS SEAS 8-11 ALONG 80W TO THE S OF 15N AND WELL DOWNSTREAM OF THE MAX WINDS. EXPECT THE FRONTAL TROUGH/SHEAR LINE TO GRADUALLY DISSIPATE TONIGHT WITH SURFACE WINDS ACROSS THE NW CARIBBEAN BECOMING SE 10-15 KT. THE GALE WILL PERSIST ALONG THE NW COAST OF COLOMBIA THROUGH SUNRISE SAT THEN DIMINISH WITH THE NOCTURNAL MAX ONLY 25 KT ON SUN NIGHT INTO MON AND MON NIGHT INTO TUE. LONG PERIOD NW SWELLS...WITH COMBINED SEAS TO 10 FT...ARE FORECAST TO PROPAGATE THROUGH THE TROPICAL N ATLC...AND NE CARIBBEAN PASSAGES THROUGH SAT NIGHT THEN SUBSIDE ON SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST WHICH IS A GFS/ECMWF BLEND. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST. MEDIUM-HIGH CONFIDENCE. A FRONTAL TROUGH OR SHEAR LINE EXTENDING NE-SW FROM 26N55W TO HISPANIOLA SHOULD LOSE IDENTITY EARLY SAT. A SURFACE RIDGE WILL EXTEND NE-SW ACROSS THE FAR NW WATERS TODAY WITH ANTICYCLONIC E- SE SURFACE WINDS AT 15-20 KT ACROSS THE AREA EXCEPT FOR 20-25 KT WITHIN ABOUT 300 NM W AND NW OF THE DISSIPATING FRONT. THIS SHOULD MAINLY BE A PROBLEM ACROSS ATLC APPROACH TO WINDWARD PASSAGE. THESE WINDS WILL DIMINISH TONIGHT AS THE SLY FLOW N OF THE RIDGE INCREASES TO 20-25 KT IN ADVANCE OF A COLD FRONT MOVING OFF THE GA COAST EARLY SAT NIGHT ACCOMPANIED BY A 20-25 KT SW-W-NW WIND SHIFT ACROSS THE WATERS TO THE N OF 27N. THE FRONT WILL REACH FROM BERMUDA TO THE WINDWARD PASSAGE LATE SUN NIGHT THEN STALL ALONG 27N55W TO HISPANIOLA ON TUE NIGHT. SURFACE HIGH PRESSURE WILL MOVE OFF THE S CAROLINA COAST ON MON EVENING AND SHIFT E TO NEAR 31N72W ON TUE NIGHT WITH A RIDGE EXTENDING W TO SE GA. EXPECT COMBINED SEAS OF 8 FT OR GREATER TO SHIFT E ACROSS THE WATERS N OF 26N THROUGH TUE NIGHT WITH SEAS SUBSIDING TO 3-5 FT W OF 75W ON TUE NIGHT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W INCLUDING COLOMBIA BASIN... GALE WARNING EARLY TODAY INTO SAT. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 NELSON. NATIONAL HURRICANE CENTER.