000 AGXX40 KNHC 190803 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 350 AM EDT MON AUG 19 2013 UPDATED TO INCLUDE NEW LOW FEATURE ALONG GULF OF MEXICO STATIONARY FRONT 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 MODEL RUNS REMAIN ON PACE WITH CONTINUED WESTWARD FORECAST MOTION OF SURFACE TROUGH ANALYZED AT 06 UTC FROM 28N92W TO 26N93W TO 19N94W. FOR GRIDS BLENDED GFS/ECMWF WITH HIGH CONFIDENCE. ADJUSTED SEAS 2 FT HIGHER THAN MWW3 GUIDANCE OVER MUCH OF THE CENTRAL AND EASTERN GULF FOR THE PERIODS OF TONIGHT THROUGH TUE EVENING. THE MAIN FEATURE ACROSS THE AREA CONTINUES TO BE THE ABOVE MENTIONED SURFACE TROUGH OVER THE WESTERN GULF. A PERSISTENT WEAK STATIONARY FRONT IS ANALYZED OVER THE FAR NW GULF AT 06Z FROM EASTERN LOUISIANA SW TO NEAR 29N95W. THE EXTREME NORTHERN PORTION OF A FAR WESTERN CARIBBEAN TROPICAL WAVE IS MOVING W THROUGH NW CUBA. THE WESTERN EXTENSION OF ATLC HIGH PRES EXTENDS SW ACROSS CENTRAL FLORIDA...AND TO NEAR 27N90W. LATEST BUOY OBSERVATIONS AND A COUPLE OF RECENT ASCAT PASSES REVEAL GENTLE TO MODERATE WINDS THROUGHOUT WITH PREVAILING DIRECTION FROM E-SE IN THE CENTRAL AND EASTERN PORTIONS...AND NE-E WINDS W OF THE TROUGH. A SMALL AREA OF GENTLE WINDS FROM THE SE-S IS LOCATED IN THE N CENTRAL PORTION. THE BUOY OBSERVATIONS ALONG WITH A FEW SHIP REPORTS SHOWS SEAS IN THE 3-4 FT RANGE IN THE CENTRAL AND SE PORTIONS...AND LOWER SEAS OF 2-3 FT ELSEWHERE. THE ASCAT PASS FROM 0354 UTC DEPICTS THE NE TO SE WIND SHIFT ACROSS THE TROUGH RATHER NICELY. THE ASCAT PASS FROM 0212 UTC ALSO SUGGESTED THAT A NE TO SE WIND SHIFT IS ASSOCIATED WITH THE TROPICAL WAVE JUST SE OF THE GULF. AS ADVERTISED IN PREVIOUS FORECASTS...THE SURFACE TROUGH WILL MOVE WILL MOVE INLAND THE NE MEXICO AND S THROUGH MON BEFORE MOVING INLAND THE TEXAS AND MEXICO COASTS TONIGHT. NO MAJOR IMPACT TO WINDS AND SEAS IS EXPECTED FROM THIS TROUGH. THE WESTERN PORTION OF THE STATIONARY FRONT WILL GRADUALLY DISSIPATE THROUGH TUE. THE HIGH PRES RIDGE OVER THE EASTERN GULF WILL BUILD FURTHER WESTWARD ACROSS THE NORTHERN WATERS ONCE THE TROUGH MOVES INLAND WITH GENERALLY LIGHT WINDS AND LOW SEAS THROUGHOUT INTO FRI. THE NORTHERN EXTENSION OF THE TROPICAL WAVE WILL MOVE ACROSS THE YUCATAN CHANNEL TODAY...THEN REACH THE S CENTRAL GULF AREA TONIGHT. IT WILL MOVE NW REACHING THE EASTERN PORTION OF THE WESTERN GULF BY TUE EVENING BEFORE IT BECOMES DIFFUSE. EXPECT SCATTERED SHOWERS AND A FEW TSTMS WITH POSSIBLE GUSTY WINDS WITH THIS FEATURE. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS WITH HIGH CONFIDENCE. RATHER QUIET CONDITIONS PREVAIL THROUGHOUT THE AREA. A PARTIAL ASCAT PASS FROM 0230 UTC SUGGESTED THAT THE EARLIER ONGOING NE-E 20-25 KT TRADES IN THE S CENTRAL PORTION OF THE CARIBBEAN HAVE DIMINISHED TO 15-20 KT. SEAS THERE HAVE SUBSIDED TO 5-6 FT. THE 0232 UTC ASCAT PICKED UP ON E 20 KT WINDS OVER THE SOUTHERN PORTION OF THE GULF OF HONDURAS. ELSEWHERE...LIGHTER TRADES EXIST WITH SPEEDS OF 10-15 KT. SEAS ELSEWHERE ARE IN THE RANGE OF 4-5 FT...EXCEPT FOR 2-3 FT IN THE SE PART OF THE CARIBBEAN...AND FOR 5-7 FT SEAS OVER MUCH OF THE NORTHERN AND CENTRAL PORTIONS OF THE TROPICAL N ATLC WATERS. A TROPICAL WAVE FROM NW CUBA TO TO NE HONDURAS IS MOVING W AT ANALYZED ALONG 77W S OF 21N IS MOVING W AT 10-15 KT. THIS WAVE WILL MOVE NW ACROSS THE YUCATAN PENINSULA AND YUCATAN THIS AFTERNOON AND EVENING. SCATTERED SHOWERS AND ISOLATED TSTMS ARE N OF 19N W OF 83W...AND SHIFTING WESTWARD WITH THE WAVE. ANOTHER TROPICAL WAVE ALONG 66W IS ALSO MOVING W AT 10-15 KT. THIS WAVE WILL MOVE ACROSS THE REMAINDER OF THE EASTERN CARIBBEAN SEA TODAY...ACROSS THE CENTRAL CARIBBEAN TUE AND WED...AND THROUGH THE WESTERN CARIBBEAN THU AND FRI...BUT LIKE THE FIRST WAVE IT SHOULD BE RATHER WEAK AS IT PROGRESSES FURTHER W ACROSS THAT PART OF THE SEA. EXPECT A POSSIBLE BRIEF OCCURRENCE OF NE-E 20- 25 KT WINDS IN THE FAR SW CARIBBEAN SEA NEAR THE COAST OF COLOMBIA BEHIND THIS WAVE WITH SEAS BUILDING TO POSSIBLY 7 OR 8 FT. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: PREVIOUS FORECAST BLENDED WITH LATEST GFS WITH HIGH CONFIDENCE. A RIDGE EXTENDS FROM NEAR BERMUDA SW TO ACROSS CENTRAL FLORIDA. THE RIDGE WILL BE THE DOMINANT FEATURE ACROSS THIS AREA THROUGH MOST OF THIS FORECAST PERIOD KEEPING AN E-SE WIND FLOW OF MODERATE SPEEDS THROUGHOUT...EXCEPT IN THE FAR NW PORTION WHERE GENTLE SE-S WINDS ARE NOTED. THE BUOYS THROUGHOUT ALONG WITH A FEW SHIP OBSERVATIONS ARE REPORTING SEAS OF 3-5 FT...EXCEPT FOR LOWER SEAS OF 2-3 FT IN THE NW PORTION AND 4-6 FT E OF THE BAHAMAS...EXCEPT FOR A SMALL POCKET OF HIGHER 6-7 FT SEAS BETWEEN THE SE BAHAMAS AND 67W WHERE A TIGHTER PRES GRADIENT EXISTS ALLOWING FOR E WINDS THERE OF 20 KT. THIS TIGHTER PRES GRADIENT IS FOUND BETWEEN THE NORTHERN PORTION OF THE CARIBBEAN TROPICAL WAVE ALONG 66W...AND THE RIDGE TO ITS N. THE WAVE WILL CONTINUE WESTWARD MOVING THROUGH THE REMAINDER OF THE FAR SOUTHERN WATERS THROUGH THROUGH FRI. IT WILL ALSO BE FOLLOWED BY A SURGE OF INCREASED E WINDS OF ABOUT 20 KT...AND SEAS OF AROUND 7 OR 8 FT. THE RIDGE IS FORECAST TO SHIFT TO JUST N OF THE AREA TUE...THEN BACK S THU AND FRI. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER AGUIRRE. NATIONAL HURRICANE CENTER.