000 AGXX40 KNHC 251030 AAA MIMATS MARINE WEATHER DISCUSSION...UPDATED NWS NATIONAL HURRICANE CENTER MIAMI FL 630 AM EDT WED APR 25 2012 UPDATED CARIBBEAN SEA SECTION TO INCLUDE MENTION OF MODEL DEPICTION OF A CARIBBEAN LOW IN THE NEAR FUTURE MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... THE HIGH CENTER THAT WAS OVER THE NW GULF THE LAST FEW DAYS HAS NOW SHIFTED E TO THE CENTRAL PORTION NEAR 26N87W AS 1019 MB WITH A RIDGE EWD TO ACROSS S FLORIDA...AND ANOTHER ONE SW TO THE FAR SW GULF. BUOY OBSERVATIONS SHOW MUCH LIGHTER WINDS ACROSS THE ENTIRE GULF AS COMPARED TO PAST FEW DAYS. WITH THE HIGH CENTER NOW HAVING MOVED E...WINDS ARE HAVE BECOME SLY AT 5-10 KT EXCEPT SE TO S AT 15-20 KT IN THE FAR WRN WATER. E OF THE HIGH...WINDS ARE NW TO N AT 5-10 KT EXCEPT NW 10-15 KT IN THE FAR NE GULF. THE BUOYS ARE REPORTING SEAS OF 2-3 FT IN GENERAL EXCEPT 3-5 FT IN THE FAR WRN WATERS FROM 22N TO 27N W OF 94W. THE 1019 MB HIGH CENTER WILL MOVE TO INLAND TO W CENTRAL FLORIDA TODAY...THEN SHIFT TO E OF FLORIDA AND INTO THE WRN ATLANTIC THIS AFTERNOON AND EVENING WITH A RIDGE EXTENDING W TO THE CENTRAL TEXAS COAST. THIS PATTERN WILL ALLOW FOR SE RETURN FLOW TO INCREASE IN THE WRN GULF DUE TO THE TIGHTENING PRES GRADIENT BETWEEN THE HIGH AND DEEPENING LOW PRES IN THE SRN PLAINS. SEAS BUILD TO 6-9 FT IN THE FAR WRN GULF FROM 24N TO 28N TONIGHT AND CONTINUE INTO LATE SAT BEFORE SUBSIDING SOME INTO SUN AS THE RIDGE THEN SHIFTS SOME TO THE N. HOWEVER THE PRES GRADIENT WILL BE TIGHT ENOUGH SAT AND SUN TO ALLOW FOR SE WINDS TO INCREASE TO 20 KT FROM W TO E ACROSS MOST OF THE GULF. GFS INDICATES THAT WINDS BACK TO THE NE IN THE FAR ERN PORTION BY SUN IN RESPONSE TO AN APPROACHING W ATLC TROUGH. GFS GUIDANCE APPEARS TO BE THE STRONGEST WITH THESE WINDS...WHERE OTHER MODELS SHOW VERY LITTLE IF ANY WIND SHIFT TO THE NE. WILL LEAN TO THE MORE TAMER SOLNS OF THE OTHER NWP MODELS REGARDING THESE WINDS IN THE E GULF FOR DAY 5. PER WAVEWATCH GUIDANCES WILL FORECAST LOW SEA THROUGHOUT DURING THE PERIOD...EXCEPT IN THE FAR WRN PORTION UNDER THE INCREASING SE RETURN FLOW AS DESCRIBED ABOVE. SW NORTH ATLC S OF 31N W OF 65W... THE PRELIMINARY 6 UTC SURFACE ANALYSIS HAS A STATIONARY FRONT EXTENDING FROM 26N65W SW TO THE ERN SECTION OF THE DOMINICAN REPUBLIC. A SURFACE TROUGH IS BEHIND THE FRONT EXTENDING FROM 31N68W TO THE NEAR THE SE BAHAMAS...WHILE A RIDGE ALONG 28N ASSOCIATED WITH E GULF HIGH CENTER BUILDS EWD. SATELLITE IMAGERY SHOWS SCATTERED SHOWERS AND TSTMS SE OF THE FRONT TO OVER THE FAR SE WATERS. BOTH ASCAT DATA FROM LAST NIGHT ALONG WITH RECENT AND CURRENT BUOY OBSERVATIONS REVEAL LIGHTER NW WINDS OF 10-15 KT BEHIND THE FRONT AND TROUGH...AND SE WINDS OF 10-15 KT SE OF THE FRONT. SHIP "ZCDF4" BETWEEN ANDROS ISLAND AND CENTRAL CUBA JUST RECENTLY REPORTED NE 20 KT WINDS. SHIP "8PSH" IN THE WINDWARD PASSAGE ALSO RECENTLY REPORTED 20 KT WINDS. AS A RESULT...THE PRES GRADIENT REMAINS RATHER TIGHT OVER THE FAR SRN WATERS. LATEST BUOY OBSERVATIONS AND SEA STATE ANALYSIS FROM OPC SHOW SEAS NOW HAVING SUBSIDED TO 9 FT IN THE FAR N CENTRAL PORTION AND TO 3-4 FT MOST EVERYWHERE ELSE. GLOBAL MODELS SUGGEST THAT THE STATIONARY FRONT WILL GRADUALLY LOSE ITS IDENTITY THROUGH THE NEXT 48 TO 72 HRS. A REMNANT TROUGH FEATURE IS DEPICTED IN THE GUIDANCE...MOST NOTABLY BY THE GFS MODEL...THAT TRACKS WWD OVER THE NEXT FEW DAYS. FOR THIS SCENARIO WILL LEAN TOWARDS THE MORE WEAKER ECMWF SOLN WITH SPEED OF THE TROUGH SINCE IT IT TOO FAST WITH THE WWD MOTION...BUT WILL RELY ON GFS FOR ASSOCIATED WINDS IN TIGHTER GRADIENT ELY FLOW. WILL DEPICT A TROUGH FEATURE ON THE FORECAST GRAPHICAL PRODUCTS TO REACH A PSN FROM SE BAHAMAS TO ERN CUBA THU...FROM CENTRAL BAHAMAS TO CENTRAL CUBA FRI...AND WRN BAHAMAS TO WRN CUBA BY LATE SAT WHERE IT SLOWS DOWN AS IT APPROACHES S FLORIDA. FOR NOW WILL FORECAST ELY WINDS OF 20 KT OVER THE SRN PORTION W AND E OF THIS FEATURE IN THE MID TO LONG TERM PERIODS OF THE FORECAST. WILL CLOSELY MONITOR FUTURE MODEL TRENDS AS TO HOW THEY CARRY THIS FEATURE OVER THE NEXT SEVERAL DAYS BEFORE IT IS DESCRIBED MORE SPECIFICALLY IN FORECASTS. THE E GULF HIGH CENTER WILL SLIDE EWD INTO THE FAR WRN ATLC TODAY ...AND TO THE FAR NE WATERS BY LATE TONIGHT...TO NEAR BERMUDA BY EARLY THU WITH A RIDGE EXTENDING SW TO CENTRAL FLORIDA. BY FRI EVENING...THE RIDGE WILL EXTEND FROM NEAR 30N65W TO CENTRAL FLORIDA THEN SHIFT N TO NEAR 29N SAT AND TO 30N BY SUN. A COLD FRONT WILL PASS JUST TO THE N OF THE AREA THU AND FRI. WINDS BECOME S TO SW 15-20 KT OVER THE FAR NW WATERS TONIGHT AND SPREAD E THROUGH EARLY FRI BEFORE DIMINISHING TO 10-15 KT AND REMAINING LIKE THAT ITO SUN. WINDS ELSEWHERE BECOME NE TO E 15 KT S OF THE RIDGE EXCEPT NE TO E 20 KT OVER THE SRN PORTION WITH THE TIGHTENING PRES GRADIENT BEGINNING THIS AFTERNOON AND CONTINUING INTO THE MID AND LONG TERM PERIODS AS MENTIONED ABOVE. CARIBBEAN SEA...UPDATED THE PRELIMINARY 06 UTC ANALYSIS HAS A TROUGH...THE SOUTHERN PORTION OF THE ATLC STATIONARY FRONT...EXTENDING FROM THE S CENTRAL SECTION OF HISPANIOLA SSW TO NEAR 13N75W. BUOY OBSERVATIONS ACROSS THE BASIN ARE REPORTING E TO SE WINDS OF 10-15 KT THROUGHOUT...EXCEPT W OF THE TROUGH WHERE N-NE WINDS OF 10-15 KT ARE NOTED BY BUOYS AND AN ASCAT PASS FROM JUST PAST 3 UTC LAST NIGHT. THE EXCEPTION IS JUST S OF CUBA WHERE NE 20 KT WINDS WERE INDICATED BY THE ASCAT PASS N OF 19N BETWEEN 77W AND 83W. SEAS ARE IN THE RANGES OF 3-5 FT BETWEEN 65W AND 74W...AND 2-4 FT ELSEWHERE E OF 78W. SEAS ARE 4-6 FT W OF 78W...EXCEPT 6-7 FT S OF 15N BETWEEN 74W-82W. THE TROUGH WILL TRACK TO THE W REACHING FROM NEAR THE WINDWARD PASSAGE TO 13N76W BY LATE TONIGHT ...FROM E CUBA TO 13N80W BY THU EVENING...FROM CENTRAL CUBA TO 13N82W BY FRI...AND AS A DIFFUSING TROUGH FROM WRN CUBA TO THE NW CARIBBEAN SEA SAT. THE PRES GRADIENT BETWEEN THE TROUGH AND CENTRAL ATLC HIGH PRES WILL INDUCE A LARGE FETCH OF E 20 KT WINDS IN THE WAKE OF THE TROUGH THROUGH THE PERIOD. N TO NE 20 KT WINDS AHEAD OF THE TROUGH WILL BE CONFINED TO MAINLY S OF 16N...AND TO ALONG THE COASTS OF NICARAGUA AND NE HONDURAS. NE 20-25 KT WINDS CAN BE EXPECTED THROUGH THE WINDWARD PASSAGE INTO FRI...BEFORE DIMINISHING TO NE TO E 10-15 KT FOR DAYS 4 AND 5. BY SAT AFTERNOON...WINDS BECOME E 15-20 KT OVER JUST ABOUT THE ENTIRE SEA...EXCEPT IN THE NW PORTION WHERE LIGHTER E WINDS OF 10-15 KT SHOULD BE IN PLACE THROUGH SUN WITH THE TROUGH WEAKENING. THE GLOBAL MODELS DEPICT LOW PRES MOVING OFF NW COLOMBIA AND INTO THE FAR SW CARIBBEAN THU NIGHT...AND TRACKS IN A GENERAL WNW DIRECTION THROUGH LATE SAT AS IT SLOWLY BECOMES DIFFUSE IN THE FAR W AND NW PORTION OF THE SW CARIBBEAN ALONG THE COAST OF NE HONDURAS AND NICARAGUA SAT. THIS APPEARS TO BE ON THE FAR SOUTHERN PART OF THE SURFACE TROUGH DESCRIBED ABOVE SO FOR THIS FORECAST PACKAGE WILL FOCUS ON THE TROUGH AND ASSOCIATED WINDS ON EITHER SIDE OF IT...AND AWAIT FOR MORE TIME TO PASS WITH WWD PROGRESS OF TROUGH TO PASS BEFORE ANY MENTION OF A LOW IS INTRODUCED INTO THE FORECAST. TROPICAL N ATLC S OF 19N W OF 55W... LIGHT NE TO E WINDS PREVAIL THROUGHOUT...EXCEPT IN THE FAR SRN PORTION WHERE SLIGHTER STRONGER NE WINDS OF 15-20 KT CONTINUE. SEAS IN THIS PART OF THE ATLC ARE IN THE RANGE OF 3-5 FT. LITTLE CHANGE IN CONDITIONS ARE EXPECTED INTO THU. BY THU EVENING NE TO E WINDS OF 15-20 KT MATERIALIZE ACROSS THE AREA...AND ARE EXPECTED TO LAST THROUGH SUN. SEAS ARE FORECAST TO BUILD TO 6-8 FT LATE SAT AND SUN. NOTE... EFFECTIVE APR 3, 2012 AT 1800 UTC THE OFFSHORE WATERS FORECAST ZONES CHANGED FOR THE CARIBBEAN AND SW N ATLANTIC AND THE GULF OF MEXICO. ISSUANCE TIME FOR THE GULF OF MEXICO OFFSHORE WATERS FORECASTS IS REFERENCED TO THE EASTERN TIME ZONE. FOR DETAILS SEE WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF GRIDDED MARINE OUTPUT IS AVAILABLE AT WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE (LOWER CASE). GULF OF MEXICO... .NONE. .CARIBBEAN SEA... .NONE. .TROPICAL N ATLC... .NONE. .SW N ATLC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE