000 AGXX40 KNHC 201635 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1235 PM EDT WED MAY 20 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: GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. FOR WAVE MWW3 BLENDED WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. A WEAK HIGH PRES OF 1018 MB LOCATED IN THE NE GULF DOMINATES THE REGION. THIS SYSTEM IS EXPECTED TO MEANDER OVER THE N-CENTRAL AND NE GULF THROUGH THE END OF THE WEEK AND INTO THE WEEKEND. UNDER THIS PATTERN...MAINLY GENTLE TO MODERATE E-SE WINDS WILL PREVAIL... EXCEPT IN THE NE GULF WHERE LIGHT AND VARIABLE WINDS ARE EXPECTED NEAR THE HIGH CENTER. ALSO...FRESH TO LOCALLY STRONG WINDS WILL PULSE EACH EVENING THROUGH THE EARLY MORNING HOURS NEAR AND TO THE NW OF THE YUCATAN PENINSULA DUE TO LOCAL EFFECTS INDUCE BY A THERMAL TROUGH. THESE E-SE PULSES OF 20-25 KT WILL PROPAGATE WNW ACROSS THE SW GULF OF MEXICO EAST OF AN INVERTED TROUGH DURING THE MORNING HOURS...WITH THE TROUGH LOSING IDENTITY AND WINDS DIMINISHED TO 15-20 KT BY THE LATE MORNING/EARLY AFTERNOON HOURS EACH DAY. SEAS WILL BRIEFLY BUILD TO 4-6 FT ACROSS THE SW GULF IN ASSOCIATION WITH THESE WINDS. OTHERWISE...SEAS WILL BE GENERALLY UNDER 5 FT ACROSS THE WESTERN GULF AND UNDER 4 FT ACROSS THE EASTERN GULF...WITH THE EXCEPTION OF ONLY 1-2 FT OVER THE NE WATERS DUE TO THE PRESENCE OF THE HIGH PRES CENTER. FRESH SOUTHERLY RETURN FLOW WILL SET-UP ACROSS THE WESTERN GULF DURING THE UPCOMING WEEKEND. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. FOR WAVES LATEST MWW3 BLENDED WITH PREVIOUS OFFICIAL FORECAST. HIGH CONFIDENCE. THE PRES GRADIENT BETWEEN THE RIDGE N OF AREA AND THE COLOMBIAN LOW PRES WILL CONTINUE TO SUPPORT PULSING OF FRESH TO LOCALLY STRONG TRADE WINDS NEAR THE NW COAST OF COLOMBIA MAINLY BETWEEN 0600 AND 1200 UTC...WITH SEAS OCCASIONALLY BUILDING TO 8 FT WITH THE STRONGEST WINDS. OTHERWISE...MODERATE TO FRESH TRADES WILL PREVAIL THROUGH SUN ACROSS THE REMAINDER OF THE AREA S OF 17N WHILE MODERATE TRADES ARE EXPECTED N OF 17N. WINDS AND SEAS WILL INCREASE E OF THE WINDWARD ISLANDS THU NIGHT AND PERSIST THROUGH SUN NIGHT. IN ADDITION...EXPECT INCREASING WINDS AND SEAS ACROSS THE CENTRAL CARIBBEAN AND IN THE GULF OF HONDURAS DURING THE WEEKEND AS A STRONGER HIGH PRES MOVES ACROSS THE MIDDLE ATLC STATES INTO THE WESTERN ATLANTIC. MARINE GUIDANCE SUGGESTS TRADE WINDS OF 25-30 KT AND SEAS OF 10-11 FT NEAR THE COAST OF COLOMBIA EARLY ON SUN MORNING. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GFS BLENDED WITH PREVIOUS OFFICIAL FORECAST. FOR WAVES MWW3 BLENDED WITH PREVIOUS OFFICIAL FORECAST. MEDIUM- HIGH CONFIDENCE. A COLD FRONT IS MOVING ACROSS THE NE PORTION OF THE AREA.THE FRONT WILL MOVE S REACHING 26N BY THIS MORNING WHERE IT WILL STALL AND GRADUALLY DISSIPATE THROUGH THU. OTHERWISE...1018 MB SURFACE HIGH PRES IS NEAR 28N74W AND THE LATEST OBSERVATIONS INDICATE GENTLE ANTICYCLONIC FLOW ACROSS THE REMAINDER OF THE AREA ALONG WITH 2-4 FT SEAS. AN EXCEPTION IS ACROSS THE WATERS NEAR HISPANIOLA...INCLUDING THE APPROACH TO THE WINDWARD PASSAGE WHERE THE MOST RECENT ASCAT PASS PROVIDED OBSERVATIONS OF MODERATE TO FRESH WINDS. A SURFACE TROUGH REMAINS OVER THE NW BAHAMAS GENERATING SOME SHOWER ACTIVITY. THIS TROUGH WILL DRIFT W AND DISSIPATE TODAY. THE HIGH PRES WILL DRIFT SE AND MERGE WITH THE CENTRAL ATLC RIDGE FORECAST TO BUILD BACK ACROSS THE WESTERN ATLC BY THU. A WEAK COLD FRONT WILL APPROACH THE NW WATERS LATE THU NIGHT INTO FRI...VERY SLOWLY SHIFTING E-SE THROUGH SAT WITH NEW HIGH PRES BUILDING IN BEHIND IT BY SUN. THE PRES GRADIENT WILL TIGHTEN ACROSS THE BASIN THIS WEEKEND WITH MODERATE TO LOCALLY FRESH NE-E WINDS EXPECTED AND SEAS BUILDING TO 4-6 FT N OF 27N. A SURFACE TROUGH WILL MOVE ACROSS THE WATERS S OF 27N SAT THROUGH SUN WITH WINDS SHIFTING TO E-SE IN ITS WAKE. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 DGS. NATIONAL HURRICANE CENTER.