000 AGXX40 KNHC 010633 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 233 AM EDT MON JUL 1 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 AND ECMWF. PREVIOUS FORECAST BLENDED WITH TAFB NWPS FOR WAVE HEIGHTS. HIGH CONFIDENCE. A RIDGE EXTENDS FROM THE STRAITS OF FLORIDA ALONG 24N FROM WEAK 1011 MB HIGH PRES IN THE W CENTRAL GULF NEAR 24N95W. THIS RIDGE IS SHIFTED S RELATIVE TO ITS NORMAL POSITION (OVER THE NORTHERN GULF) DUE TO A BROAD DEEP LAYER TROUGH AMPLIFYING OVER THE MISSISSIPPI VALLEY. THIS UPPER TROUGH NOW EXTENDS SOUTHWARD THROUGH THE CENTRAL GULF TO THE YUCATAN PENINSULA. THIS PATTERN IS MAINTAINING GENERALLY LIGHT WINDS AND 1 TO 3 FT SEAS ACROSS THE BASIN W OF 87W. E OF 87W...DYNAMICS ALOFT ARE ENHANCING SCATTERED MODERATE CONVECTION...ESPECIALLY IN THE SE GULF WHERE 10-15 KT (HIGHER IN STRONGEST CONVECTION) AND 2-4 FT SEAS ARE OCCURRING. A WEAK COLD FRONT ASSOCIATED WITH THE UPPER TROUGH HAD PUSHED INTO THE FAR NW AND N CENTRAL GULF HAS RETREATED SLIGHTLY BACK TOWARD THE COAST WHILE STALLING OUT OVER THE PAST FEW HOURS AS THE SUPPORTING UPPER PATTERN HAS ALSO STALLED AND WILL BECOME MORE BROAD EARLY THIS WEEK...LEAVING MAINLY LIGHT SW TO W WINDS ALOFT. AS THIS CONTINUES INTO THE WEEK THE FRONT WILL REMAIN STALLED IN THE SAME GENERAL AREA THROUGH TONIGHT...THEN WILL PUSH BACK JUST INLAND AS A WARM FRONT TUE...DISSIPATING ALTOGETHER BY MID WEEK. MEANWHILE THE NORTHERN PORTION OF A TROPICAL WAVE EXTENDS TO THE YUCATAN CHANNEL FROM THE NW CARIBBEAN SEA AND WILL CONTINUE W TO THE YUCATAN PENINSULA THROUGH TODAY. GLOBAL MODELS CONTINUE TO INDICATE THE POTENTIAL FOR WEAK LOW PRES TO FORM IN THE FAR SW GULF BY MID WEEK AS THE REMNANTS OF THIS WAVE IN THE FORM OF A TROUGH CONTINUE WESTWARD. THE RIDGE MENTIONED ABOVE WILL LIFT BACK TO THE N THROUGH MID WEEK FOLLOWING THE DISSIPATION OF THE WEAK FRONT OVER THE NORTHERN GULF...AND AHEAD OF THE ADVANCING TROUGH/TROPICAL WAVE EMERGING OUT OF YUCATAN. LIGHT WINDS AND SEAS WILL PREVAIL INTO MID WEEK. SE WINDS WILL INCREASE OVER THE S CENTRAL GULF BY LATE WED IN THE WAKE OF THE TROUGH/TROPICAL WAVE AND AS THE RIDGE SHIFTS N. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS AND ECMWF. PREVIOUS FORECAST BLENDED WITH TAFB NWPS FOR WAVE HEIGHTS. HIGH CONFIDENCE. BUOY OBSERVATIONS AND SCATTEROMETER DATA OVER THE PAST SEVERAL HOURS INDICATE MODERATE TO FRESH TRADE WINDS ACROSS THE BASIN AS RIDGING N OF THE REGION HAS WEAKENED ALLOWING FOR THE PRES GRADIENT TO RELAX SLIGHTLY. THE SOUTHERN PORTION OF A TROPICAL WAVE EXTENDS ONSHORE OVER NICARAGUA AND HONDURAS WHILE THE NORTHERN PORTION CONTINUES OVER WATER INTO THE NW CARIBBEAN AND GULF OF HONDURAS TO THE YUCATAN CHANNEL. A SECOND TROPICAL WAVE IS IN THE E CARIBBEAN ALONG 68W. THIS WAVE IS INTERACTING WITH AN UPPER LOW CENTERED WELL NE OF THE VIRGIN ISLANDS NEAR 26N62W... WITH AN UPPER TROUGH EXTENDING SW FROM THE UPPER LOW TO THE N CENTRAL COAST OF VENEZUELA. THE POSITION OF THE UPPER TROUGH FRAMES THE AREAS OF CONVECTION OVER THE CARIBBEAN...WITH NEARLY CLOUD FREE SKIES BETWEEN 70W AND 80W...WITH MODERATE TO STRONG CONVECTION ASSOCIATED WITH THE WESTERN WAVE N OF 18N W OF 80W. CONVECTION ASSOCIATED WITH THE EASTERN WAVE IS NEARLY NON-EXISTENT OTHER THAN SOME SCATTERED SHOWERS MOVING OVER THE LESSER ANTILLES AS UPPER LEVEL WESTERLY SHEAR TAKES ITS TOLL ON THE WAVE. GLOBAL MODEL CONSENSUS SHOWS THE WESTERN WAVE LOSING DEFINITION AS IT DRIFTS W OVER THE NEXT SEVERAL DAYS...EVENTUALLY AS A TROUGH MOVING THROUGH THE YUCATAN PENINSULA TONIGHT INTO TUE. THE EASTERN WAVE WILL SIMILARLY DEAMPLIFY AS IT SHIFTS W ACROSS THE CARIBBEAN AND WILL EVENTUALLY MERGE WITH THE WESTERN WAVE BY THU. TRADE WIND FLOW OVER THE S CENTRAL CARIBBEAN WILL START TO INCREASE TONIGHT FOLLOWING THE PASSAGE OF THE SECOND WAVE. A THIRD TROPICAL WAVE WILL APPROACH THE SOUTHERN TROPICAL N ATLC WATERS NEAR 55W BY THU. ...SW N ATLANTIC W OF 55W INCLUDING THE BAHAMAS... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS AND ECMWF. PREVIOUS FORECAST BLENDED WITH WAVEWATCH FOR WAVE HEIGHTS. HIGH CONFIDENCE. AN ATLC RIDGE EXTENDS FROM THE N CENTRAL ATLC THROUGH THE NORTHERN BAHAMAS TO CENTRAL FL NEAR DAYTONA BEACH. HIGH MOISTURE VALUES AND A CONVERGENCE OF SE AND SW LOW LEVEL FLOW...AND DIVERGENT WINDS ALOFT ARE ALLOWING ONGOING AREAS OF CONVECTION ACROSS THE NW BAHAMAS AND OFF THE NE AND CENTRAL COASTS OF FL. BUOY AND SCATTEROMETER DATA INDICATE THE SOUTHERLY FLOW IS REACHING 20 KT N OF 29N W OF 77W...BETWEEN THE RIDGE AND A DEEP LAYER TROUGH TO THE W. SEAS ARE GENERALLY 4 TO 6 FT OUTSIDE THE BAHAMAS...WITH UP TO 7 FT IN THE AREA OF STRONGER 20 KT WINDS. OPERATIONAL MODELS SHOW THE TROUGHING BECOMING LESS AMPLIFIED AND WEAKENING OVER THE NEXT COUPLE OF DAYS ALLOWING THE STRONGER WINDS IN THE NW PORTION OF THE BASIN TO DIMINISH WITH THE RIDGE CONTINUING TO SHIFT N. MEANWHILE S OF 24N/23N...MODERATE TRADES WILL FRESHEN THROUGH MID WEEK AS A TROPICAL WAVE MOVES THROUGH THE CENTRAL CARIBBEAN WITH THE NORTHERN PORTION OF THE WAVE MANAGING TO EXTEND INTO THE WATERS S OF 22N. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER LEWITSKY. NATIONAL HURRICANE CENTER.