000 AGXX40 KNHC 301849 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 247 PM EDT THU JUL 30 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: 12Z GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. FOR WAVEHEIGHTS USED EVEN BLEND OF 12Z MWW3 AND 12Z NWPS PARAMETERS INTO PREVIOUS OFFICIAL. HIGH CONFIDENCE. LATEST PRES ANALYSIS SHOWS THE WEAK HIGH PRES RIDGE SUPPRESSED TO THE SOUTHERN PORTION OF THE GULF...WHILE A TROUGH DROPS SW INTO THE CENTRAL GULF FROM THE SE U.S. THE TROUGH IS ACTING UPON A VERY DEEP MOIST AND UNSTABLE AIR MASS IN PLACE OVER THE EASTERN AND CENTRAL GULF PORTIONS RESULTING IN SCATTERED AND TSTMS THERE. GUSTY WINDS CAN BE EXPECTED WITH THIS ACTIVITY AS IT IS EXPECTED TO LINGER INTO EARLY NEXT WEEK WHILE SHIFTING SLIGHTLY MORE TO THE NE GULF. THE CURRENT RELATIVELY LOW SEA STATE OF 1-2 FT THROUGHOUT IS FORECAST BY WAVEWATCH GUIDANCE TO CHANGE VERY LITTLE THROUGH THE PERIOD...WITH THE EXCEPTION OF THE SW GULF (ZONE 23) WHERE THE DAILY NOCTURNAL TROUGH THAT MOVES OFF THE YUCATAN PENINSULA MAY INCREASE SEAS THERE AT NIGHT TO AROUND 5 FT DURING THE PERIOD. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 12Z GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. FOR WAVEHEIGHTS USED EVEN BLEND OF 12Z MWW3 AND 12Z NWPS PARAMETERS INTO PREVIOUS OFFICIAL. HIGH CONFIDENCE. THE 1452 UTC HIGH RESOLUTION ASCAT-B SHOWED A SMALL SWATH OF NE 25-30 KT WINDS RIGHT ALONG THE COAST OF COLOMBIA BETWEEN 74W AND 76W. THE SAME ASCAT PASS SHOWED A LARGE AREA OF MOSTLY FRESH NE WINDS OVER MUCH OF THE CENTRAL CARIBBEAN S OF 16N BETWEEN 70W- 76W...AND MUCH LIGHTER WINDS OF GENTLE TO MODERATE INTENSITY OVER THE WESTERN CARIBBEAN SEA. LATEST BUOY AND ALTIMETER DATA SHOW SEAS IN THE 6-9 FT RANGE OVER THE EASTERN PORTION OF THE WESTERN CARIBBEAN 16N BETWEEN 80W-81W. SEAS ELSEWHRE ARE LOWER...IN THE 4-5 FT RANGE...EXCEPT FOR 2-3 FT SEAS S OF W OF 85W AND N OF 20N W OF 79W. SEAS ARE 5-6 FT IN THE TROPICAL N ATLC ZONES. MAINLY FRESH TRADES WILL CONTINUE OVER THE CENTRAL CARIBBEAN THROUGH THE PERIOD WITH POCKETS OF STRONG NE TRADES NEAR THE COAST OF COLOMBIA. A TROPICAL WAVE NEAR 72W WILL MOVE ACROSS THE REMAINDER OF THE EASTERN CARIBBEAN TONIGHT...THEN ACROSS THE CENTRAL CARIBBEAN FRI...AND WESTERN CARIBBEAN FRI NIGHT SUN NIGHT. ANOTHER TROPICAL WAVE CURRENTLY OVER THE CENTRAL TROPICAL ATLC WILL APPROACH 55W EARLY ON SAT...AND MOVE ACROSS THE REST OF THE TROPICAL N ATLC THROUGH SAT NIGHT...THEN ACROSS THE EASTERN CARIBBEAN SUN THROUGH MON...THE EASTERN PART OF THE WESTERN CARIBBEAN TUE AND THE REST OF THE WESTERN LATE TUE AND WED. LOOKING AHEAD...A BROAD LOW PRESSURE LOCATED A FEW HUNDRED MILES SW OF THE CAPE VERDE ISLANDS HAS THE POTENTIAL FOR SOME SLOW DEVELOPMENT INTO EARLY NEXT WEEK AS IT MOVES IN A GENERAL WESTWARD TRACK. IT IS EXPECTED TO BE LOCATED TO THE E OF THE TROPICAL N ATLC ON TUE. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: 12Z GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. FOR WAVEHEIGHTS USED EVEN BLEND OF 12Z MWW3 AND 12Z NWPS PARAMETERS INTO PREVIOUS OFFICIAL. HIGH CONFIDENCE. THE 18 UTC PRELIMINARY ANALYSIS HAS A 1012 MB LOW NEAR 31.5N76.5W WITH A TRAILING TROUGH TO 28.5N80W. HIGH PRES IS PRESENT ELSEWHERE ACROSS THE BASIN...WEAKER OVER THE WESTERN HALF OF THE AREA. BUOY AND ATLTIMETER REPORTS SHOWS SEAS IN THE 3- 5 FT RANGE E OF THE BAHAMAS. SEAS ARE LOWER...1-2 FT...W OF THE BAHAMAS. THE EXCEPTION IS IN THE NW PORTION NEAR THE LOW WHERE SEAS ARE 6-9 FT...AND WHERE WINDS ARE S-SW 20-30 KT WITHIN 90 NM E OF THE TROUGH N OF 28N. THE FORECAST FOR THIS PERIOD REMAINS PRACTICALLY UNCHANGED FROM THE RECENT ONES...THE LOW PRES WILL CONTINUE TO PULL AWAY FROM THE AREA TONIGHT INTO FRI AS A TROUGH TRAILS SW FROM THE LOW BUT WILL ALSO LIFTS N OF THE AREA LATER TONIGHT WITH THE ASSOCIATED TIGHT GRADIENT E OF THE LOW AND TROUGH WILL RELAXING. THE HIGH PRESENT ELSEWHERE ACROSS THE AREA WILL REBUILD AS A RIDGE NEAR 28N TONIGHT AND CHANGE LITTLE THROUGHOUT THE PERIOD. FRESH TRADES WILL DEVELOP ALONG THE N COAST OF HISPANIOLA EACH NIGHT THROUGH TUE NIGHT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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 AGUIRRE. NATIONAL HURRICANE CENTER.