000 AGXX40 KNHC 290640 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 240 AM EDT SAT JUN 29 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 NWPS FOR WAVE HEIGHTS. HIGH CONFIDENCE. A 1014 MB HIGH PRES CENTER NEAR 25N92W ANCHORS THE SUBTROPICAL RIDGE ACROSS THE CENTRAL GULF OF MEXICO. THIS IS MAINTAINING GENERALLY LIGHT WINDS AND 1 TO 2 FT SEAS ACROSS THE BASIN. THE EXCEPTION IS OVER THE FAR NE GULF WHERE A MID LEVEL SHORT WAVE TROUGH IS ENHANCING CLUSTERS OF CONVECTION AND MAINTAINING 10 TO 15 KT WITH 2 TO 4 FT SEAS. MEANWHILE OPERATIONAL MODELS REMAIN IN DECENT AGREEMENT SHOWING A LONG WAVE TROUGH AMPLIFYING ACROSS THE DEEP SOUTH STATES AND INTO THE NORTHERN GULF. THIS WILL RESULT IN A WEAK COLD FRONT STALLING ALONG THE NW AND N CENTRAL GULF COASTLINES EARLY SUN...THEN REACHING AS FAR AS THE WESTERN FLORIDA PANHANDLE TO SOUTH TEXAS BY EARLY MON...BEFORE STALLING AGAIN AND BECOMING DIFFUSE BY MID WEEK. THE RIDGE WILL SHIFT SOUTH AHEAD OF THE FRONT...THEN WILL DRIFT BACK TO THE N AS THE FRONT WEAKENS BY MID WEEK. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS AND ECMWF. PREVIOUS FORECAST BLENDED WITH NWPS FOR WAVE HEIGHTS. HIGH CONFIDENCE. RECENT SCATTEROMETER DATA CONTINUE TO INDICATE FRESH TO STRONG TRADE WINDS OVER THE S CENTRAL AND SE CARIBBEAN...BETWEEN A RIDGE N OF THE AREA AND A TROPICAL WAVE IN THE WESTERN CARIBBEAN REACHING FROM JUST S OF WESTERN CUBA TO JUST E OF THE COAST OF NICARAGUA. THE SOUTHERN PORTION OF THIS WAVE WILL SHIFT W INTO CENTRAL AMERICA THIS WEEKEND WITH THE NORTHERN PORTION STILL EXTENDING INTO THE NW CARIBBEAN...WHERE IT WILL STALL AS IT INTERACTS WITH THE MONSOON TROUGH. THE TRADE WINDS WILL DIMINISH OVER THE CENTRAL CARIBBEAN THROUGH THE DAY TODAY AS A SECOND TROPICAL WAVE APPROACHING THE WINDWARD ISLANDS PUSHES INTO THE EASTERN CARIBBEAN. THIS WAVE IS ALREADY STARTING TO INTERACT WITH AN UPPER LOW CENTERED N OF THE VIRGIN ISLANDS NEAR 22N63W...AND IS PRODUCING LARGE AREAS OF CONVECTION FROM THE NE COAST OF VENEZUELA NORTHWARD TO NEAR ST. LUCIA AND MARTINIQUE. WHILE THIS WAVE WILL AMPLIFY WITH THE ASSISTANCE OF THE UPPER LOW IN THE SHORT TERM AS IT MOVES ACROSS THE EASTERN CARIBBEAN THROUGH SUN...IT WILL THEN START TO FLATTEN MON AS IT SHIFTS INTO THE CENTRAL CARIBBEAN. BOTH THE GFS AND ECMWF INDICATE THIS TREND BUT MORE SO THE GFS. THE WAVE ALMOST LOSES IDENTITY AS IT PUSHES INTO THE NW CARIBBEAN AND NORTHERN CENTRAL AMERICA THROUGH MID WEEK...BECOMING ABSORBED IN A DEVELOPING PATTERN OVER THE EASTERN PACIFIC. AT ANY RATE...TRADE WINDS WILL INCREASE AGAIN EARLY IN THE WEEK...THEN GRADUALLY DIMINISHING THROUGH WED/THU AS THE WAVE WEAKENS WHILE CONTINUING WESTWARD ALLOWING FOR THE PRES GRADIENT TO RELAX SLIGHTLY. SEAS WILL BUILD TO 8 TO 10 FT WITH THE INCREASE OF THESE WINDS. MEANWHILE MODELS ARE IN DECENT AGREEMENT SHOWING THE APPROACH OF A THIRD TROPICAL WAVE INTO THE TROPICAL N ATLC WATERS LATE WED INTO THU. THIS WAVE IS CURRENTLY ANALYZED NEAR 28W...BUT IS POORLY DEFINED. IF MODEL GUIDANCE IS CORRECT THIS FEATURE WILL BECOME WELL AMPLIFIED AS IT TRACKS WESTWARD OVER THE NEXT SEVERAL DAYS. ...SW N ATLANTIC W OF 55W INCLUDING THE BAHAMAS... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS AND ECMWF. PREVIOUS FORECAST BLENDED WITH NWPS FOR WAVE HEIGHTS. HIGH CONFIDENCE. AN ATLC RIDGE EXTENDS FROM 1023 MB HIGH PRES NEAR 31N57W TO FLORIDA NEAR 27N80W. ASCAT AND EARLIER WINDSAT SCATTEROMETER DATA INDICATED MAINLY MODERATE WINDS ALONG THE RIDGE AXIS. HOWEVER A MID LEVEL SHORT WAVE TROUGH DIGGING THROUGH THE SOUTHEAST U.S. STATES CONTINUES TO SUPPORT A SURFACE TROUGH ALONG THE CAROLINA COAST. THIS PRES PATTERN IS SETTING UP A FAIRLY TIGHT PRES GRADIENT ESPECIALLY IN THE NW PORTION WHERE FRESH S-SW WINDS ARE ALREADY OCCURRING...STRONGER N OF 31N. MODERATE TRADES WILL PERSIST ELSEWHERE. A 06 UTC SHIP OBSERVATION NEAR 30.5N79W REPORTED SEAS TO 7 FT. ELSEWHERE SEAS ARE 3-5 FT OUTSIDE OF THE BAHAMAS WITH 1-3 FT INSIDE THE BAHAMAS. A COLD FRONT WILL MOVE THROUGH THE SOUTHEAST U.S. STATES BEFORE STALLING AND BECOMING DIFFUSE EARLY NEXT WEEK. THIS WILL MAINTAIN THE MODERATE TO FRESH SW FLOW OVER OFFSHORE WATERS ZONES AMZ111 AND AMZ113. TRADES S OF THE RIDGE WILL INCREASE SLIGHTLY EARLY NEXT WEEK AS A TROPICAL WAVE PUSHES ACROSS THE CARIBBEAN...TIGHTENING THE PRES GRADIENT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER LEWITSKY. NATIONAL HURRICANE CENTER.