000 AGXX40 KNHC 231834 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 234 PM EDT TUE AUG 23 2016 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: GLOBAL MODEL CONSENSUS. MEDIUM-HIGH CONFIDENCE. A TROPICAL WAVE WILL PASS THROUGH THE BAY OF CAMPECHE TODAY AND IS ALREADY ENHANCING CONVECTION. OTHERWISE...A THERMAL TROUGH WILL DEVELOP OVER THE YUCATAN PENINSULA DURING THE LATE AFTERNOONS AND CONTINUE INTO THE EARLY EVENINGS. EXPECT FRESH NE-E WINDS TO DEVELOP EACH DAY THROUGH WEDNESDAY ALONG THE NW COAST OF THE WESTERN YUCATAN PENINSULA BEGINNING IN THE LATE AFTERNOONS...AND ENDING BEFORE MIDNIGHT EACH NIGHT AS THE INVERTED TROUGH MOVES W- NW ACROSS THE SW GULF WATERS...ACCOMPANIED BY A ENE-ESE 15-20 KT WIND SHIFT...AND 4-5 FT SEAS. THE TROUGH WILL LOSE IDENTITY NEAR 22N94W BY LATE EACH MORNING. THE THU...FRI AND SAT EVENTS WILL BE CONSIDERABLY WEAKER WITH ONLY A MODERATE WIND SHIFT EXPECTED ALONG THE TROUGH. ELSEWHERE...A SURFACE HIGH OVER THE NORTH CENTRAL GULF WILL SHIFT NORTH OF THE AREA LATER TODAY...LEAVING A NE TO SW RIDGE ACROSS THE NORTHERN GULF WATERS ON THU THROUGH FRI NIGHT. MAINLY MODERATE EASTERLY TO SOUTHEASTERLY FLOW IS EXPECTED ACROSS THE CENTRAL AND NORTHERN GULF DURING THIS TIME FRAME. THE RIDGE WILL WEAKEN OVER THE WEEKEND WHICH WILL RESULT IN MAINLY GENTLE TO MODERATE WINDS LEADING INTO SUNDAY. UNCERTAINTY INCREASES OVER THE EASTERN GULF EARLY NEXT WEEK AS A TROPICAL WAVE AND ASSOCIATED LOW PRESSURE CURRENTLY APPROACHING THE LEEWARD ISLANDS MAY APPROACH THE REGION. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. MEDIUM CONFIDENCE. A TROPICAL LOW IS CURRENTLY NEAR 16.5N56.5W ALONG A TROPICAL WAVE. CONVECTION IS SLOWLY BECOMING BETTER ORGANIZED AND GUIDANCE FAVORS TROPICAL CYCLONE DEVELOPMENT AS THE LOW TRACKS NW ACROSS THE FAR NE CARIBBEAN PASSING NEAR THE VIRGIN ISLANDS TONIGHT...AND PASSING N OF PUERTO RICO ON WED...WITH THE STRONGEST WINDS OVER THE NE QUADRANT. HEAVY RAINFALL WITH LOCALIZED FLOODING WILL BE POSSIBLE OVER THE ISLANDS...ESPECIALLY WHERE THE SYSTEM INTERACTS WITH HIGHER TERRAIN. FRESH TO STRONG WINDS ARE FORECAST ALONG THE NORTHERN COAST OF COLOMBIA THROUGH TONIGHT. THEN...AS SURFACE RIDGING WEAKENS IN RESPONSE TO THE PASSAGE OF THE TROPICAL LOW TO THE NORTH OF THE REGION...THE PRESSURE GRADIENT WILL RELAX WHICH WILL ALLOW WINDS OVER THE SOUTH CENTRAL CARIBBEAN TO DIMINISH TO MODERATE TO FRESH THROUGH THE END OF THE WEEK. TROPICAL CYCLONE GASTON IS EXPECTED TO PASS E OF THE AREA BUT LONG PERIOD SWELLS RESULTING IN COMBINED SEAS OF 7-10 FT WILL PROPAGATE INTO THE TROPICAL WATERS N OF 15N E OF 60W ON FRI AND SAT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. LOW-MEDIUM CONFIDENCE. SWELL OF 8 TO 10 FT ASSOCIATED WITH THE REMNANTS OF FIONA WILL GRADUALLY SUBSIDE BELOW 8 FT THROUGH TONIGHT. TROPICAL CYCLONE GASTON WILL PASS EAST OF THE FORECAST ZONES BETWEEN 55W AND 60W BEGINNING ON FRI NIGHT THROUGH THE WEEKEND. THIS PATH IS A CHANGE TO THE EAST FROM THE PREVIOUS FORECAST. THIS SCENARIO WOULD HAVE MUCH LESS OF AN IMPACT ACROSS THE ATLANTIC ZONES...HOWEVER WILL STILL DIRECTLY AFFECT THE REGION IN OUR HIGH SEAS. IN OUR EASTERN ZONES...EXPECT MAINLY LONG PERIOD SWELL OF 8 TO 10 FT TO PROPAGATE WESTWARD FROM THE SYSTEM BEGINNING FRIDAY. THE LOW PRESSURE SYSTEM AND WAVE CURRENTLY TO THE EAST OF THE WINDWARD ISLANDS HAS THE POTENTIAL TO DEVELOP INTO A TROPICAL CYCLONE LATER THIS WEEK. GALE FORCE WINDS WILL BECOME LIKELY OVER THE SOUTHERN ATLANTIC ZONES...INCLUDING THE BAHAMAS...AS THE SYSTEM CROSSES THE AREA THE NEXT SEVERAL DAYS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS II COLLABORATION CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ117...BAHAMAS INCLUDING CAY SAL BANK... GALE CONDITIONS POSSIBLE SAT INTO SAT NIGHT. .AMZ119...ATLANTIC FROM 22N TO 27N E OF BAHAMAS TO 70W... GALE CONDITIONS POSSIBLE THU INTO SAT NIGHT. .AMZ121...ATLANTIC FROM 22N TO 27N BETWEEN 65W AND 70W... GALE WARNING THU. GALE CONDITIONS POSSIBLE THU INTO THU NIGHT. .AMZ123...ATLANTIC S OF 22N W OF 70W INCLUDING APPROACHES TO THE WINDWARD PASSAGE... GALE CONDITIONS POSSIBLE THU. .AMZ125...ATLANTIC S OF 22N BETWEEN 65W AND 70W INCLUDING PUERTO RICO TRENCH... GALE WARNING WED NIGHT INTO THU. GALE CONDITIONS POSSIBLE THU. $$ *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 LATTO. NATIONAL HURRICANE CENTER.