000 AGXX40 KNHC 271836 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 236 PM EDT THU AUG 27 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: LATEST GFS BLENDED WITH LATEST FORECAST. NWPS USED FOR WAVE PARAMETERS. HIGH CONFIDENCE THROUGH SAT...THEN LOW- MEDIUM CONFIDENCE. A STATIONARY FRONT EXTENDS FROM THE FLORIDA BIG BEND AREA TO THE CENTRAL GULF NEAR 25N87W TO THE W CENTRAL GULF NEAR 23N94W. THE FRONT WILL GRADUALLY BECOME DIFFUSE THROUGH FRI. A TROUGH REMAINS IN PLACE OVER S FLORIDA INTO THE SE GULF AHEAD OF THE FRONT AND SCATTERED TO NUMEROUS SHOWERS WITH ISOLATED TSTMS ARE OCCURRING ACROSS THE BASIN SE-S OF THE FRONT MAINLY OVER THE FLORIDA KEYS AND OFFSHORE OVER THE GULF STREAM. WINDS AND SEAS REMAIN FAIRLY SUBDUED ACROSS THE GULF WITH LITTLE CHANGE EXPECTED THROUGH SAT. THE MAIN ISSUE FOR SUN AND MON CONTINUES TO BE THE TRACK AND DEVELOPMENT OF TROPICAL STORM WARNING ERIKA...NOW MOVING W ACROSS THE LEEWARD ISLANDS. THE CURRENT FORECAST SHOWS SLOW DEVELOPMENT OF ERIKA AS IT MOVES WNW TOWARD OR OVER THE BAHAMAS. ERIKA IS EXPECTED TO STRENGTHEN TO A HURRICANE AS IT STARTS TO MAKE A TURN TO THE NORTH OVER THE NORTHERN BAHAMAS IN A WEAKNESS IN THE RIDGE STARTING SUNDAY...ALTHOUGH UNCERTAINTY REMAINS AT THIS TIME AS TO THE EXACT TRACK AND INTENSITY FOR SUNDAY. PLEASE SEE THE LATEST FORECAST REASONING UNDER AWIPS/WMO HEADERS MIATCDAT5/WTNT45 KNHC FOR MORE DETAILS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: 12 UTC GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST...OFFICIAL FORECAST FOR ERIKA WITH HAND EDITS. NWPS USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. THE CENTER OF TROPICAL STORM WARNING ERIKA IS MOVING ACROSS THE FAR NE CARIBBEAN CURRENTLY. STRONG SHOWERS AND THUNDERSTORMS ARE NOTED NEAR THE CENTER OF ERIKA AND WITHIN 150 NM IN THE SE QUADRANT OF THE STORM. ASIDE FROM LOCALIZED SQUALLS...THE MAIN MARINE IMPACTS OF WINDS AND SEAS ARE OVER ATLC WATERS WITHIN 270 NM NE OF THE LEEWARD ISLANDS...WELL AWAY FROM THE CENTER OF ERIKA. THE STORM IS EXPECTED TO CONTINUE TO MOVE WNW AND PASS OVER THE VIRGIN ISLANDS AND PUERTO RICO TONIGHT THROUGH FRI NIGHT. LIGHT TO MODERATE WINDS PERSIST ELSEWHERE ACROSS THE BASIN CURRENTLY. TRADE WIND FLOW WILL INCREASE OFF WESTERN VENEZUELA BY LATE FRI AS RIDGING BUILDS N OF THE AREA IN THE WAKE OF ERIKA. THE AREA OF FRESH TO STRONG TRADES WILL SPREAD ACROSS THE S CENTRAL CARIBBEAN THROUGH SAT NIGHT...THEN DIMINISH AS THE NEXT TROPICAL WAVE FOLLOWING ERIKA MOVES ACROSS THE CARIBBEAN BASIN. THE EXPECTED TRACK AND INTENSITY OF ERIKA OVER THE FAR WESTERN ATLC WILL KEEP THE SUBTROPICAL RIDGE WEAK AND DISPLACED INTO EARLY NEXT WEEK. THIS WILL PREVENT ANY LARGE SCALE INCREASE IN TRADES SUN THROUGH TUE EXCEPT FOR BRIEF OVERNIGHT PULSES OFF WESTERN VENEZUELA AND NE COLOMBIA. MODERATE TRADES ELSEWHERE. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST...OFFICIAL FORECAST FOR ERIKA WITH HAND EDITS. NWPS USED FOR WAVE PARAMETERS. LOW TO MEDIUM CONFIDENCE. SHOWERS AND THUNDERSTORM CONTINUE OVER THE BAHAMAS AND OFF THE EAST COAST OF FLORIDA LONG A PERSISTENT TROUGH REACHING FROM 31N76W TO THE UPPER FLORIDA KEYS. FARTHER TO THE SE...A 14 UTC ASCAT PASS INDICATED 20 TO 30 KT WINDS WITHIN 270 NM N OF THE LEEWARD ISLANDS...ON THE NORTH END OF TROPICAL STORM ERIKA CURRENTLY MOVING ACROSS THE FAR NE CARIBBEAN. WINDS TO TROPICAL STORM FORCE CAN BE EXPECTED LATE THIS EVENING OVER ATLC WATERS N OF THE VIRGIN ISLANDS AS THE CENTER OF ERIKA MOVE ACROSS THE VIRGIN ISLANDS AND PUERTO RICO TONIGHT THROUGH FRI NIGHT. ERIKA IS EXPECTED TO DEVELOP GRADUALLY INTO A STRONG HURRICANE THROUGH LATE FRI AS IT CONTINUES WNW MAINLY N OF HISPANIOLA TOWARD THE TURKS AND CAICOS ISLANDS AND SE BAHAMAS...THEN ON TO THE CENTRAL BAHAMAS THROUGH SAT. THERE REMAINS SOME UNCERTAINTY REGARDING THE EXACT TRACK AND INTENSITY OF ERIKA LATE SAT INTO SUN AS ERIKA REACHES A WEAKNESS IN THE RIDGE AND STARTS TO MAKE A TURN TOWARD THE NORTH...POSSIBLY STRENGTHENING TO A HURRICANE AS IT MOVES INTO THE NW BAHAMAS THEN NORTHWARD ALONG THE EAST COAST OF FLORIDA. PLEASE SEE THE LATEST FORECAST REASONING UNDER AWIPS/WMO HEADERS MIATCDAT5/WTNT45 KNHC FOR MORE DETAILS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ025...OFFSHORE WATERS LEEWARD ISLANDS... TROPICAL STORM WARNING TODAY INTO TONIGHT. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ123...ATLANTIC S OF 22N W OF 70W INCLUDING APPROACHES TO THE WINDWARD PASSAGE... TROPICAL STORM WARNING FRI NIGHT. .AMZ125...ATLANTIC S OF 22N BETWEEN 65W AND 70W INCLUDING PUERTO RICO TRENCH... TROPICAL STORM WARNING FRI INTO FRI NIGHT. $$ *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 CHRISTENSEN. NATIONAL HURRICANE CENTER.