000 AGXX40 KNHC 180536 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 136 AM EDT WED MAR 18 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. TAFB NWPS USED FOR WAVE PARAMETERS. MEDIUM-HIGH CONFIDENCE. NE 10-15 KT WINDS ARE OBSERVED OVER THE E BAY OF CAMPECHE ORIGINATING FROM TUE EVENINGS LOCAL ENHANCEMENT ALONG THE W COAST OF THE YUCATAN PENINSULA. THESE WINDS WILL PROPAGATE W ACROSS EARLY THIS MORNING...AND DISSIPATE OVER THE CENTRAL BAY OF CAMPECHE BY LATE MORNING. THIS PATTERN IS EXPECTED TO REPEAT EACH EVENING...WITH GUIDANCE SUGGESTING THE EVENTS WILL BE A LITTLE STRONGER WITH 15-20 KT WINDS ENHANCED WINDS BEGINNING ON THU EVENING. A SURFACE HIGH OVER THE NW GULF WATERS WILL SHIFT SE TO OVER THE CENTRAL GULF LATER TODAY WHERE IT WILL MEANDER THROUGH EARLY FRI...THEN SHIFT NW OF THE AREA. GUIDANCE IS FLUCTUATING ON THE STRENGTHS AND TRACKS OF TWO WEAK COLD FRONTS FOR THE NEXT FEW DAYS. USING A MODEL BLEND...THE CURRENT SCENARIO IS A WEAK COLD FRONT WILL MOVE E THROUGH THE FAR NE GULF WATERS ON FRI ACCOMPANIED BY A SW-W-NW 5-10 KT WIND SHIFT. THE RIDGE WILL WEAKEN ON SAT AS ANOTHER COLD FRONT MOVES INTO THE NW GULF MOVES E REACHING FROM MS DELTA TO THE CENTRAL BAY OF CAMPECHE ON SUN...AND FROM THE W FL PANHANDLE TO THE E BAY OF CAMPECHE AT SUNRISE ON MON. GUIDANCE HAS BACKED OFF CONSIDERABLY SINCE YESTERDAY...AND NOW SUGGESTS THE ASSOCIATED SW-W-NW WIND SHIFT ALONG THE FRONT WILL ONLY BE IN THE 5-10 KT RANGE TILL THE FRONT IS RE-ENFORCED ON MON AND THE GRADIENT THEN SUPPORTS NW-N 10-15 KT CONDITIONS OVER ALL THE GULF WATERS N OF 25N W OF THE FRONT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. TAFB NWPS USED FOR WAVE PARAMETERS. MEDIUM-HIGH CONFIDENCE. WEAK ATLC RIDGING N OF THE AREA COMBINED WITH LOW PRES OVER NW COLOMBIA WILL SUPPORT STRONG 20-25 KT NE WINDS WITHIN 90 NM OF THE COAST OF COLOMBIA EACH NIGHT THROUGH THE PERIOD... DIMINISHING TO 15-20 KT BY LATE MORNING. MODERATE TRADES EXPECTED ELSEWHERE ACROSS THE ENTIRE AREA THROUGH THU MORNING... THEN FRESH NE-E TRADES WILL DEVELOP ACROSS THE TROPICAL WATERS E OF THE WINDWARDS ON THU EVENING...WITH SEAS BUILDING TO 5-8 FT BRIEFLY ON FRI. THE GRADIENT WILL RELAX ON SAT AND SUN WITH MODERATE TRADES FORECAST E OF THE WINDWARDS AGAIN. FRESH ESE TRADES WILL DEVELOP ACROSS THE GULF OF HONDURAS ON THU...FRI... SAT AND SUN NIGHTS...WITH GUIDANCE HINTING AT STRONG E WINDS BRIEFLY ON SAT NIGHT. REINFORCING N SWELL WILL PROPAGATE S INTO THE ATLC WATERS E OF THE LEEWARDS ON FRI EVENING BUILDING COMBINED SEAS TO 6-8 FT. THESE CONDITIONS WILL SPREAD FURTHER S ACROSS THE ATLC WATERS E OF THE WINDWARDS LATE SAT..THEN GRADUALLY SUBSIDE BELOW 8 FT ON SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. TAFB NWPS USED FOR WAVE PARAMETERS. MEDIUM CONFIDENCE. A FRONTAL TROUGH WILL DISSIPATE ACROSS THE TROPICAL WATERS N OF THE VIRGIN ISLANDS THROUGH TONIGHT. A SURFACE HIGH IS CENTERED NEAR 25N69W WITH A RIDGE EXTENDING E AND W ALONG 25N. LIGHT NE-E WINDS ARE OBSERVED S OF THE RIDGE...EXCEPT BECOMING MODERATE TO THE S OF 21N TO INCLUDE THE ATLC APPROACHES TO THE CARIBBEAN PASSAGES. SOUTHERLY FLOW N OF THE RIDGE IS IN THE 15-20 KT RANGE...EXCEPT 20-25 KT ACROSS THE WATERS N OF 30N...ALL AHEAD OF A COLD FRONT THAT HAS ENTERED THE NW WATERS N OF THE RIDGE AXIS. THE NORTHERLY FLOW N OF 30N BEHIND THE FRONT WILL INCREASE TO 20-25 KT BRIEFLY TODAY...THEN DIMINISH TONIGHT AS THE FRONT REACHES FROM 31N58W TO THE ACROSS THE NW BAHAMAS TO NEAR FT PIERCE FL. THE GRADIENT WILL RELAX TONIGHT WITH FRONT STALLING FROM 30N55W TO 27N65W TO FT PIERCE FL. THE SEGMENT OF THE FRONT W OF 70W WILL LIFT RAPIDLY NE THU AS A WARM FRONT ACROSS THE WATERS N OF THE BAHAMAS...WITH E-SE FLOW INCREASING TO 15-20 KT ACROSS THE WATERS NE OF THE FRONT AND W OF 70W. ANOTHER COLD FRONT...BUT ONLY ACCOMPANIED BY A 10 KT SW-W-NW WIND SHIFT... WILL ENTER THE WATERS N OF THE BAHAMAS ON THU NIGHT...REACH FROM 31N74W TO THE NW BAHAMAS ON FRI NIGHT THEN ACCELERATE E PASSING BERMUDA SAT EVENING. THIS FRONT WILL STALL FROM 31N60W TO THE NW BAHAMAS ON SUN...THEN LIFT N AS A WARM FRONT AHEAD OF YET ANOTHER COLD FRONT ON MON. LIKELY SEE ADJUSTMENTS TO THE STRENGTH AND TRACK OF THESE WEEKEND FRONTS IN FUTURE MODEL RUNS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.