000 AGXX40 KNHC 181812 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 212 PM EDT THU SEP 18 2014 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 PREVIOUS/OFFICIAL FORECAST. MWW3 USED FOR WAVE PARAMETERS. MEDIUM TO HIGH CONFIDENCE. A 1015 MB HIGH PRES IS IN THE CENTRAL GULF NEAR 26N90W AND IS FORECAST TO DISSIPATE IN ABOUT 6-12 HOURS. A FRONTAL TROUGH EXTENDS FROM NEAR FORT MYERS TO 28N87W. THIS TROUGH IS GENERATING SCATTERED MODERATE CONVECTION MAINLY NEAR 26N86W. WEAK PRES GRADIENT DOMINATES THE GULF REGION WITH VARIABLE WINDS AT 5-10 KT IN THE NE HALF OF THE GULF ALONG WITH SEAS OF 2 FT OR LESS...AND E-SE WINDS AT 10-15 KT ACROSS THE SW HALF OF THE GULF WITH SEAS OF 1-3 FT. THE FRONTAL TROUGH IS FORECAST TO STALL IN THE E CENTRAL OR SE GULF THROUGH TONIGHT...THEN WILL GRADUALLY LIFT BACK TO THE N INTO THE WEEKEND MEANDERING ALONG 26N/27N. EXPECT MODERATE TO LOCALLY FRESH ELY WINDS N OF THE TROUGH AXIS AND MAINLY ACROSS THE N WATERS ON FRI AND SAT AS A STRONGER HIGH PRES BUILDS ACROSS THE SE CONUS. IN ADDITION...EXPECT MODERATE TO FRESH WINDS NEAR THE COAST OF YUCATAN DURING THE EVENINGS DUE TO LOCAL EFFECTS. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. MWW3 USED FOR WAVE PARAMETERS. HIGH CONFIDENCE. IN THE CARIBBEAN...WEAK RIDGE N OF AREA IS PRODUCING ONLY GENTLE TO MODERATE TRADE WINDS WITH SEAS GENERALLY UNDER 4 FT BASED ON BUOYS AND A FEW SHIP OBSERVATIONS. WINDS SLIGHTLY INCREASE ACROSS THE SOUTH-CENTRAL CARIBBEAN TO 15-20 KT WITH SEAS TO AROUND 5 FT. A WEAK PRESSURE PATTERN WILL REMAIN ACROSS THE REGION THROUGH AT LEAST EARLY NEXT WEEK. NE-E TRADES AT 10-20 KT WILL PREVAIL IN THE S CENTRAL WATERS...LOCALLY HIGHER NEAR THE COAST OF COLOMBIA AND AT NIGHT IN THE GULF OF HONDURAS. SEAS WILL BE 4-6 FT NEAR THE COAST OF COLOMBIA AND IN THE GULF OF HONDURAS...WITH MAINLY 1-3 FT ELSEWHERE. A TROPICAL WAVE OVER THE EASTERN CARIBBEAN ALONG 64W WILL MOVE ACROSS THE CENTRAL CARIBBEAN TONIGHT THROUGH FRI NIGHT...THEN WILL WEAKEN AND BECOME HARDER TO TRACK AS IT CONTINUES WESTWARD. IN THE TROPICAL N ATLC...A TROPICAL WAVE CURRENTLY ALONG 43W/44W S OF 20N WILL MOVE ACROSS THE TROPICAL N ATLC WATERS SAT AND SAT NIGHT...THEN INTO THE E CARIBBEAN SUN AND SUN NIGHT. TRADES AT 10-15 KT WILL PREVAIL THROUGH THE FORECAST PERIOD ALONG WITH 4-6 FT SEAS. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. MWW3 USED FOR WAVE PARAMETERS. MEDIUM CONFIDENCE. A FRONTAL TROUGH EXTENDS FROM 31N73W TO SOUTH FLORIDA. FRESH TO STRONG SWLY FLOW IS NOTED N OF 30N AND AHEAD OF THE TROUGH AXIS TO ABOUT 64W WITH SEAS OF 5-7 FT. THIS SYSTEM IS GENERATING SOME SHOWER AND TSTM ACTIVITY...PARTICULARLY ACROSS THE WATERS N OF 27N. THE TROUGH WILL STALL FROM BERMUDA TO S FLORIDA ON FRI...THEN MOVE BACK TO THE NW FRI NIGHT. THE TROUGH WILL THEN STALL OVER THE NW PORTION SAT AND SAT NIGHT WITH LOW PRES DEVELOPING ALONG IT E OF NORTHERN FLORIDA. THE LOW WILL MOVE N OF THE AREA SUN WHILE A TRAILING TROUGH LINGERS IN THE NW PORTION. AS THE LOW PRES DEVELOPS...EXPECT INCREASING NE WINDS NW AND N OF THE LOW CENTER WITH BUILDING SEAS OF 5-8 FT. THE FORECAST DEPENDS ON HOW STRONG THE LOW DEVELOPS. THIS LOW PRES AREA WILL HAVE SOME POTENTIAL TO ACQUIRE TROPICAL OR SUBTROPICAL CHARACTERISTICS WHILE IT MOVES NORTHEASTWARD NEAR OR OFFSHORE OF THE SOUTHEASTERN COAST OF THE UNITED STATES. CURRENTLY...MARINE GUIDANCE SUGGESTS FRESH TO STRONG WINDS OF 20-30 KT AND SEAS OF 7-10 FT AHEAD OF THE FRONTAL TROUGH SAT NIGHT THROUGH SUN...AND MODERATE TO FRESH NLY WINDS BEHIND THE FRONTAL TROUGH WITH SEAS TO NEAR 8 FT. ACROSS THE REMAINDER OF THE FORECAST WATERS...LITTLE CHANGE IN THE MARINE CONDITIONS IS EXPECTED WITH 5-15 KT RETURN FLOW AND 3-5 FT SEAS EXPECTED... EXCEPT 2 FT OR LESS INSIDE THE BAHAMAS. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *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.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER GR. NATIONAL HURRICANE CENTER.