000 AGXX40 KNHC 230704 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 304 AM EDT FRI SEP 23 2016 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: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE THROUGH MON...THEN MEDIUM. WEAK HIGH PRESSURE CENTERED OVER THE NORTH-CENTRAL GULF COAST WILL SLOWLY DRIFT TO THE NORTHEASTERN GULF THROUGH THE WEEKEND. THIS PATTERN WILL SUPPORT LIGHT TO GENTLE WINDS OVER THE EASTERN GULF WITH SEAS OF 1 TO 2 FT...AND MAINLY GENTLE TO MODERATE WINDS OVER THE WESTERN GULF WITH SEAS OF 2 TO 4 FT. THE EXCEPTION WILL BE A THERMAL TROUGH THAT WILL DEVELOP EACH AFTERNOON AND EVENING OVER THE YUCATAN PENINSULA THAT WILL MOVE WESTWARD OVER THE BAY OF CAMPECHE OVERNIGHT. THIS TROUGH WILL SUPPORT FRESH EAST TO NORTHEAST WINDS EACH NIGHT THROUGH SUNDAY NIGHT. UNCERTAINTY IN THE FORECAST INCREASES EARLY NEXT WEEK AS MODELS DIVERGE ON THEIR TIMING AND STRENGTH OF A POTENTIAL COLD FRONT ENTERING THE NORTHWEST GULF SOMETIME BETWEEN MONDAY NIGHT AND TUESDAY. THE LATEST GFS HAS BACKED OFF QUITE A BIT ON THE STRENGTH OF THIS FRONT...WITH THE NEWEST FORECAST PACKAGE BRINGING MAXIMUM WINDS BEHIND THE FRONT TO 25 KT. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE THROUGH TUE...THEN LOW TO MEDIUM. SUBTROPICAL RIDGING NORTH OF THE CARIBBEAN IS DISRUPTED DUE TO THE PRESENCE OF TROPICAL STORM KARL. THIS WILL RESULT IN MAINLY GENTLE TO MODERATE TRADE WINDS OVER THE CARIBBEAN THROUGH THIS EVENING. AS KARL GAINS LATITUDE AND THE SUBTROPICAL RIDGE BUILDS BACK NORTH OF THE CARIBBEAN...THE TRADES WILL INCREASE SLIGHTLY WITH MODERATE TO FRESH EASTERLIES EXPECTED OVER THE SOUTH CENTRAL CARIBBEAN BEGINNING TONIGHT THROUGH TUE. A SURFACE TROUGH OVER THE CENTRAL TROPICAL ATLANTIC WILL APPROACH THE LESSER ANTILLES SATURDAY NIGHT WHICH WILL BRING AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY TO THE ISLANDS SATURDAY THROUGH SUNDAY. A TROPICAL WAVE CURRENTLY NEARING THE AFRICAN COAST WILL QUICKLY CROSS THE TROPICAL ATLANTIC OVER THE WEEKEND AND APPROACH OUR TROPICAL ATLANTIC ZONES EARLY NEXT WEEK...THEN THE EASTERN CARIBBEAN THE MIDDLE OF NEXT WEEK. SOME OF THE GLOBAL MODEL SOLUTIONS INDICATE THIS WAVE MAY ORGANIZE INTO A TROPICAL LOW AS IT REACHES THE LESSER ANTILLES AND EASTERN CARIBBEAN MID WEEK. HOWEVER...THIS PORTION OF THE FORECAST IS LOWER CONFIDENCE IN PART DUE TO THE SPREAD IN MODEL FORECAST SOLUTIONS THIS FAR OUT IN TIME. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: GLOBAL MODEL CONSENSUS. HIGH CONFIDENCE. A STATIONARY FRONT OVER THE EXTREME NORTHWESTERN WATERS WILL DISSIPATE INTO A TROUGH OVER THE NEXT 24 HOURS. TROPICAL STORM KARL IS JUST EAST OF OUR NORTHEASTERN ZONES AND WILL CONTINUE TO MOVE NORTH NORTH-WEST THROUGH THE NEXT 24 HOURS...NEARING ZONE AMZ115 THROUGH TONIGHT...BEFORE THE STORM ACCELERATES AWAY FROM OUR FORECAST WATERS OVER THE WEEKEND. TROPICAL STORM CONDITIONS ARE LIKELY OVER THE EASTERN PORTION OF ZONE AMZ121 THIS MORNING...AND AMZ115 THIS MORNING THROUGH EARLY MORNING SATURDAY. LARGE SWELL FROM KARL WILL IMPACT THESE 2 ZONES THROUGH TONIGHT BEFORE SUBSIDING THROUGH SATURDAY. LONG PERIOD SWELL OF 5 TO 7 FT FROM KARL WILL PROPAGATE AS FAR WEST AS 78W NORTH AND EAST OF THE BAHAMAS THIS WEEKEND. WEAK HIGH PRESSURE WILL BUILD ACROSS THE AREA IN THE WAKE OF KARL THIS WEEKEND WITH GENTLE TO MODERATE WINDS AND SEAS MAINLY BETWEEN 3 TO 5 FT ACROSS THE ZONES SUNDAY AFTERNOON THROUGH MONDAY NIGHT. BY MONDAY NIGHT...A COLD FRONT MAY CROSS OUR NORTHERN WATERS BRINGING WITH IT MODERATE TO FRESH EAST TO NORTHEAST WINDS. .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS II COLLABORATION CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... .AMZ115...ATLANTIC FROM 27N TO 31N BETWEEN 65W AND 70W... TROPICAL STORM WARNING EARLY TODAY INTO TONIGHT. .AMZ121...ATLANTIC FROM 22N TO 27N BETWEEN 65W AND 70W... TROPICAL STORM WARNING EARLY TODAY. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER LATTO. NATIONAL HURRICANE CENTER.