000 AGXX40 KNHC 111657 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1257 PM EDT SAT APR 11 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 WHICH WAS A GFS/ECMWF BLEND. TAFB NWPS USED FOR WAVE PARAMETERS. MEDIUM-HIGH CONFIDENCE. A COLD FRONT IS STALLING FROM THE FL PANHANDLE TO SE TX. SHOWERS/TSTMS ACCOMPANY THE FRONT WITH EMBEDDED AREAS OF PATCHY FOG OVER THE NW WATERS...ALL DENOTED IN THE WEATHER GRIDS. A N-S TROUGH IS DISSIPATING OVER THE BAY OF CAMPECHE ACCOMPANIED BY A E-SE 10-15 KT WIND SHIFT. AN E-W RIDGE EXTENDS ACROSS THE E- CENTRAL AND CENTRAL GULF WATERS...WITH 5-10 KT ANTICYCLONIC FLOW EVERYWHERE ELSE SE OF THE FRONT. THE RIDGE WILL PUSH THE FRONT INLAND BY EARLY SUN WITH SE 10-15 KT FLOW SETTING UP ACROSS THE GULF WATERS N OF 24N THROUGH WED NIGHT...THEN THE GRADIENT WILL TIGHTEN AHEAD OF A WEAK COLD FRONT MOVING SE OVER THE NW WATERS ON THU. EXPECT THIS AFTERNOONS HEAT TROUGH OVER THE YUCATAN PENINSULA TO SET UP 15- 20 KT NE FLOW ALONG THE W COAST OF THE YUCATAN PENINSULA THIS EVENING...WITH THE PULSE PROPAGATING W ACROSS THE SW GULF ON SUN MORNING...AND GRADUALLY DIMINISHING BY SUN AFTERNOON. EXPECT SUN EVENINGS THERMAL ENHANCEMENT TO BE IN THE 20-25 KT RANGE...WITH SE 20-25 KT WINDS PROPAGATING W ACROSS THE S-CENTRAL GULF ON MON MORNING. THESE EVENING EVENTS WILL BECOME MINIMAL AGAIN ON MON EVENING. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL WHICH WAS A GFS/ECMWF BLEND. TAFB NWPS USED FOR WAVE PARAMETERS. MEDIUM-HIGH CONFIDENCE. ATLC RIDGING N OF THE AREA...COMBINED WITH LOW PRES OVER NW COLOMBIA...WILL SUPPORT NEAR GALE 25-30 KT NE WINDS WITHIN 90- 120 NM OF THE COAST OF COLOMBIA TONIGHT...THEN DIMINISHING TO 20- 25 KT CONDITIONS EACH NIGHT BEGINNING ON SUN NIGHT AS THE ATLC RIDGE GRADUALLY WEAKENS. STRONG TRADES EXPECTED ACROSS THE CENTRAL CARIBBEAN TONIGHT...THEN THE GRADIENT WILL RELAX AFTER SUN. E TRADES WILL INCREASE TO 20-25 KT ACROSS THE GULF OF HONDURAS EACH NIGHT BEGINNING ON SUN NIGHT. FRESH TRADES EXPECTED ACROSS THE TROPICAL N ATLC WATERS THROUGH THE PERIOD... EXCEPT INCREASING BRIEFLY TO STRONG OVER THE WATERS S OF 11N LATE TUE WITH SEAS BUILDING BRIEFLY TO 8 FT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL WHICH WAS A GFS/ECMWF BLEND. TAFB NWPS USED FOR WAVE PARAMETERS. MEDIUM-HIGH CONFIDENCE. A SURFACE HIGH NEAR 29N49W RIDGING WSW TO PORT CANAVERAL IS RETRACTING E AS A COLD FRONT MOVES INTO THE FAR NW WATERS ACCOMPANIED BY A SW-W-NW 10-15 KT WIND SHIFT. THE FRONT WILL REACH FROM BERMUDA TO THE NW BAHAMAS ON SUN AFTERNOON WITH NORTHERLY WINDS INCREASING TO 20-25 KT...SEAS BUILDING TO 7 FT...ACROSS THE WATERS N OF 30N W OF 72W ON SUN...THEN DIMINISHING ON SUN NIGHT AS THE FRONT SLOWS FROM 31N59W TO THE NW BAHAMAS. A RIDGE WILL DEVELOP FROM 31N70W TO FT PIERCE ON TUE THEN RETRACT E IN ADVANCE OF THE NEXT COLD FRONT MOVING OFF THE NE FL COAST ON WED. GFS GUIDANCE IS HINTING AT CYCLOGENESIS ALONG THIS FRONT ON WED NIGHT INTO THU...BUT OTHER GUIDANCE IS NOT AS AGGRESSIVE. TUTT INDUCED LOW-MID LEVEL INVERTED TROUGHS CONTINUE TO DEVELOP S OF THE SURFACE RIDGE AND PROPAGATE W ACROSS THE AREA... ACCOMPANIED BY SHALLOW CONVECTION INTRODUCED INTO WEATHER GRIDS...BUT GENERALLY DISSIPATE BEFORE REACHING THE BAHAMAS AS THE TROUGHS ENCOUNTER LESS FAVORABLE UPPER SUPPORT W OF 68W. THE GRADIENT SUPPORTS 15-20 KT TRADES S OF 23N...EXCEPT ENHANCED TO 20-25 KT ALONG THE N COAST OF HISPANIOLA AND ATLC APPROACH TO THE WINDWARD PASSAGE...DURING THE AFTERNOONS INTO THE EARLY NIGHT HOURS...WITH SEAS BUILDING TO 7 FT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 NELSON. NATIONAL HURRICANE CENTER.