000 AGXX40 KNHC 131823 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 223 PM EDT TUE AUG 13 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: PREVIOUS FORECAST BLENDED WITH LATEST GFS/ECMWF WITH HIGH CONFIDENCE THROUGH WED...THEN MEDIUM CONFIDENCE THEREAFTER. PREVIOUS FORECAST BLENDED WITH LATEST NWPS. 1016 MB HIGH PRES IS CENTERED IN THE CENTRAL GULF NEAR 27N89W WITH AN E TO W RIDGE AXIS EXTENDING ALONG 27N. AN ELONGATED UPPER LEVEL LOW EXTENDS FROM THE SE GULF TO W OF THE YUCATAN PENINSULA WITH SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING OVER THE SE AND S CENTRAL GULF. LIGHT TO MODERATE WINDS DOMINATE THE BASIN WHILE 1-3 FT SEAS HUG THE COAST WITHIN 60-120 NM WITH 3-5 FT SEAS OUTSIDE OF THAT AREA. LITTLE CHANGE IN THE WEATHER PATTERN AND CURRENT CONDITIONS IS EXPECTED THROUGH TONIGHT. A COLD FRONT WILL APPROACH THE U.S. GULF COASTAL STATES LATE TONIGHT...STALLING JUST INLAND THROUGH THE REMAINDER OF THE WEEK. ATTENTION THEN TURNS TOWARD A TROPICAL WAVE CURRENTLY APPROACHING THE NW CARIBBEAN FROM THE SE. THIS WAVE IS FORECAST TO APPROACH THE YUCATAN PENINSULA WED NIGHT WITH THE NORTHERN EXTENSION ENTERING THE S CENTRAL GULF BY THU MORNING. DISAGREEMENT WITH GLOBAL MODEL GUIDANCE SOLUTIONS REMAINS WITH RESPECT TO THE EVOLUTION OF THIS WAVE. THE GFS CONTINUES TO BREAK OFF A PIECE OF THE WAVE TAKING IT NORTHWARD AS AN UPPER TROUGH TO THE N DIGS SOUTHWARD. THE GFS APPEARS TO BE SUFFERING FROM CONVECTIVE FEEDBACK AND CONTINUES TO SHOW AT LEAST 30 KT OF WIND IN THE NE GULF ON THE SE SIDE OF DEVELOPING LOW PRES. THE REMAINDER OF GLOBAL MODEL GUIDANCE...EXCEPT FOR THE CMC...TAKES THE WAVE ON A MORE SOUTHERN TRACK ACROSS THE YUCATAN PENINSULA AND THEN SW GULF/BAY OF CAMPECHE...PUSHING INLAND OVER MEXICO THIS WEEKEND. THIS GRIDDED PACKAGE WILL CONTINUE TO SHOW A PIECE OF ENERGY BREAKING OFF FROM THE WAVE MOVING TO THE N AND NE...ALTHOUGH WINDS HAVE BEEN CAPPED AT 15-20 KT. MEANWHILE THE REMAINING WAVE AXIS CONTINUES WESTWARD CLOSE TO THE MODEL CONSENSUS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS/ECMWF WITH HIGH CONFIDENCE. PREVIOUS FORECAST BLENDED WITH LATEST NWPS. AN ELONGATED UPPER LOW CENTERED OVER THE NORTHERN COAST OF THE YUCATAN IS SUPPORTING A TROPICAL WAVE MOVING TOWARD THE NW CARIBBEAN CURRENTLY EXTENDING FROM SE CUBA TO E OF NICARAGUA NEAR 12N82W. A LARGE AREA OF NUMEROUS SHOWERS AND SCATTERED TSTMS COVERS THE WATERS WITHIN 180-300 NM EITHER SIDE OF THE WAVE. ASSOCIATED WINDS AND SEAS ARE FORECAST TO DIMINISH AND SUBSIDE AS IT CONTINUES TO THE NW TONIGHT WITH A WEAK PRES GRADIENT PRESENT IN THE NW CARIBBEAN. THE WAVE IS FORECAST TO EXIT THE NW CARIBBEAN THU AFTERNOON INTO EVENING. A MUCH WEAKER TROPICAL WAVE WAS NOTED IN THE FAR E CARIBBEAN THIS MORNING. A RECENT ASCAT PASS WENT RIGHT OVER THE WAVE WITH LITTLE INDICATION THAT THE FEATURES REMAINS AT THE SURFACE. OUTSIDE OF THE NW CARIBBEAN WAVE...MAINLY MODERATE TO LOCALLY FRESH TRADES ARE BLOWING ACROSS THE BASIN. TRADES ACROSS THE CENTRAL CARIBBEAN ARE FORECAST TO INCREASE TO FRESH TO STRONG WED THROUGH FRI AS THE PRES GRADIENT TIGHTENS WITH HIGH PRES STRENGTHENING SLIGHTLY N OF THE AREA. THIS WEEKEND THE PRES GRADIENT WILL SIGNIFICANTLY WEAKENING WITH MODERATE TRADES AND 3-5 FT SEAS DOMINATING THE CARIBBEAN AND TROPICAL N ATLC AREAS. ANOTHER TROPICAL WAVE IS FORECAST TO IMPACT THE TROPICAL N ATLC BY SAT MORNING...THEN THE E CARIBBEAN SUN. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS/ECMWF WITH HIGH CONFIDENCE. PREVIOUS FORECAST BLENDED WITH LATEST NWPS. 1019 MB HIGH PRES IS CENTERED NEAR 28N72W. LIGHT WINDS AND 2-4 FT SEAS PREVAIL ACROSS THE WATERS N OF 25N WITH MAINLY MODERATE WINDS S OF 25N. THE INTERACTION OF THE RIDGE WITH A TROPICAL WAVE MOVING THROUGH THE CENTRAL-NW CARIBBEAN IS SUPPORTING 15 TO 20 KT WINDS AND SEAS UP TO 6 FT MAINLY OVER THE APPROACHES TO THE WINDWARD PASSAGE. THE RIDGE WILL SHIFT S BY WED AS A WEAK FRONTAL BOUNDARY STALLS JUST NW-N OF THE AREA. SW WINDS WILL INCREASE SLIGHTLY OVER THE OFFSHORE WATERS OFF NE FLORIDA TODAY THROUGH THU. OTHERWISE LITTLE CHANGE IS EXPECTED THROUGH THE FORECAST PERIOD. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER LEWITSKY. NATIONAL HURRICANE CENTER.