000 AGXX40 KNHC 141823 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 223 PM EDT WED AUG 14 2013 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: PROVISIONAL NHC FORECAST USED FOR POSITION OF DEVELOPING LOW PRES. WW3 USED INITIALLY...AWAITING 18Z NWPS RUN BASED ON NHC FORECAST. LOW CONFIDENCE. A WEAK E TO W RIDGE IS IN PLACE ALONG 26N WITH LIGHT ANTICYCLONIC WINDS ACROSS THE NORTHERN WATERS AND LIGHT TO MODERATE WINDS OVER THE SOUTHERN WATERS. SEAS ARE 1-3 FT OVER THE NORTHERN GULF AND 2-4 FT OVER THE SOUTHERN WATERS. EVEN THOUGH CURRENT MARINE CONDITIONS ARE QUITE TRANQUIL... CONDITIONS ARE FORECAST TO GO DOWN HILL THROUGH THE END OF THE WEEK INTO THE WEEKEND AS LOW PRES ACCOMPANYING A TROPICAL WAVE APPROACHES THE S CENTRAL GULF FROM THE YUCATAN PENINSULA/NW CARIBBEAN. PREVIOUSLY THE GFS HAS BEEN TAKING THE LOW/WAVE ACROSS THE CENTRAL GULF WATERS TOWARD SOMEWHERE BETWEEN SE LOUISIANA AND THE FLORIDA PANHANDLE WHILE OTHER GLOBAL MODEL GUIDANCE HAS BEEN ON A PERSISTENT WESTWARD TRACK TOWARD MEXICO/SE TEXAS. THE 12Z GFS HOWEVER HAS NOW CHANGED ITS TUNE TAKING THE LOW MORE TO THE W AS WELL. THE 12Z NHC PRELIMINARY FORECAST POINTS WERE USED FOR THIS PACKAGE WHICH TAKES A LOW TOWARD S CENTRAL LOUISIANA. WINDS WERE CAPPED AT 30 KT AND SEAS AT 11/12 FT ALTHOUGH WILL AWAIT THE 18Z NWPS RUN BEFORE FINALIZING WAVE HEIGHTS. BY THE END OF THE WEEKEND INTO EARLY NEXT WEEK WEAK RIDGING WILL REBUILD ACROSS THE GULF IN THE WAKE OF THE LOW/WAVE WITH MUCH MORE TRANQUIL CONDITIONS AGAIN. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: PROVISIONAL NHC FORECAST USED FOR POSITION OF DEVELOPING LOW PRES IN NW CARIBBEAN. OTHERWISE PREVIOUS FORECAST BLENDED WITH LATEST GFS. WW3 USED INITIALLY...AWAITING 18Z NWPS RUN BASED ON NHC FORECAST. MODERATE CONFIDENCE. A TROPICAL WAVE EXTENDS FROM WESTERN CUBA TO DEVELOPING 1009 MB LOW PRES NEAR 17N83W TO 13N83W. DEEP CONVECTION HAS PERSISTED NEAR THE LOW CENTER FOR A GOOD 6-12 HOURS NOW...HOWEVER...A RECENT ASCAT PASS WENT RIGHT OVER THE LOW AND SHOWED STRAIGHT SE FLOW ACROSS THE AREA. THE PROVISIONAL NHC FORECAST TAKES THE LOW/WAVE TOWARD THE YUCATAN PENINSULA...MOVING INLAND THU. IN THE MEANTIME AT A MINIMUM FRESH TO STRONG WINDS ARE EXPECTED ON THE E SIDE OF THE LOW/WAVE ALONG WITH 8-11 FT SEAS. OTHERWISE...FRESH TO STRONG TRADES COVER THE CENTRAL ATLC WITH MODERATE TO FRESH TRADES ELSEWHERE. THE HIGHEST SEAS ARE EXPECTED TO BE NW OF THE COAST OF COLOMBIA AT THE TAIL END OF THE FETCH REGION. FRESH TO STRONG TRADES WILL SPREAD INTO THE W CARIBBEAN THROUGH THU IN THE WAKE OF THE LOW/WAVE...THEN WILL DIMINISH BY FRI MORNING AS THE PRES GRADIENT OVER THE REGION WEAKENS SIGNIFICANTLY WITH MODERATE TO LOCALLY FRESH TRADES FORECAST FOR THE REMAINDER OF THE FORECAST PERIOD. THE NEXT TROPICAL WAVE WILL ENTER THE TROPICAL N ATLC LATE FRI INTO SAT MORNING...MOVING ACROSS THE NE CARIBBEAN THROUGH SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS/ECMWF WITH HIGH CONFIDENCE. WW3 USED INITIALLY...AWAITING 18Z NWPS RUN FOR UPDATE WAVE HEIGHTS. 1028 MB HIGH PRES IS CENTERED WELL NE OF THE BASIN IN THE ATLC NEAR 34N44W WITH A RIDGE AXIS EXTENDING SW THROUGH 27N65W TO SE FLORIDA. A MID TO UPPER LEVEL LOW CONTINUES TO SPIN OVER THE NE PORTION GENERATING SCATTERED SHOWERS AND TSTMS MAINLY OVER AMZ115 AND THE NORTHERN PORTION OF AMZ121. LIGHT TO MODERATE WINDS AND 3-5 FT SEAS DOMINATE THE NORTHERN HALF OF THE AREA...EXCEPT 1-3 FT W OF THE BAHAMAS...WITH MODERATE TRADES AND 4-6 FT SEAS ACROSS THE SOUTHERN HALF. THE NORTHERN PORTION OF A TROPICAL WAVE IS FORECAST TO SKIRT THE WATERS S OF 22N THIS WEEKEND THROUGH EARLY NEXT WEEK. THE RIDGE WILL LIFT TO THE N BY THE END OF THE WEEK WITH MODERATE E-SE WINDS ACROSS THE BASIN...ALONG WITH 4-6 FT SEAS IN THE SE HALF AND 2-4 FT SEAS IN THE NW HALF. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER LEWITSKY. NATIONAL HURRICANE CENTER.