000 AGXX40 KNHC 271847 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 245 PM EDT WED APR 27 2011 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. SW N ATLC... PRELIMINARY SURFACE ANALYSIS REVEALS A 1031 MB HIGH CENTER JUST N OF THE AREA NEAR 34N57W WITH A RIDGE SW TO S FLORIDA. THIS HIGH CONTINUES TO BE IN CONTROL OF THE AREA AS IT MAINTAINS ITS GRASP ON THE WIND FLOW THROUGHOUT. BUOYS...ALONG WITH A FEW SHIP OBSERVATIONS...HAVE BEEN AND ARE CURRENTLY REPORTING E TO SE 20-25 KT WINDS S OF 26N E OF BAHAMAS AND E TO SE WINDS OF 15-20 KT ELSEWHERE EXCEPT W OF 78W WHERE A WEAKER PRES GRADIENT IS ALLOWING FOR LIGHTER SE-S WINDS OF 10-15 KT. ASCAT DATA FROM THIS MORNING SUPPORTED THESE OBSERVATIONS...ESPECIALLY OVER THE AREA E OF THE BAHAMAS FROM 20N TO 27N WHERE THE 20-25 KT WINDS ARE OCCURRING DUE TO A TIGHT PRES GRADIENT BETWEEN THE HIGH AND LOWER PRES OVER THE CARIBBEAN SEA. RECENT BUOY OBSERVATIONS FROM EARLY THIS AFTERNOON SHOW MAXIMUM SEA HEIGHTS OF 10 TO 11 FT AS REPORTED BY BUOY 41043 AT 21N65W. SEA STATE ANALYSES FROM THIS MORNING REVEALED SEAS IN THE RANGE OF 6-9 FT ELSEWHERE...EXCEPT W OF 79W WHERE THEY ARE MUCH LOWER...IN THE 2-4 FT RANGE S OF 26N...AND 3-5 FT N OF 26N. LATEST VIS AND IR SATELLITE IMAGERY CONTINUE TO SHOW CLUSTERS OF SHOWERS AND TSTMS MOVING NWD OVER MUCH OF THE WESTERN WATERS S OF 29N BETWEEN 67W AND 76W AS A WEAK MID/UPPER LEVEL TROUGH IN THIS AREA CONTINUES TO AID THIS ACTIVITY. GUSTY WINDS CAN BE EXPECTED WITH THE SHOWERS AND TSTMS. THE HIGH CENTER WILL REMAIN WILL ABOUT STATIONARY THROUGH THU MORNING BEFORE WEAKENING AS A COLD FRONT MAKES HEADWAY THROUGH THE GULF OF MEXICO. PREVIOUS FORECAST THINKING STILL LOOKS GOOD FOR THIS FORECAST TIME FRAME AS LATEST RUNS OF THE GLOBAL MODELS FROM THIS MORNING IS IN REASONABLE AGREEMENT WITH NEAR FUTURE SCENARIO SHAPING UP WITH THE COLD FRONT ENTERING THE NW PORTION OF THIS ZONE DURING EARLY THU EVENING. AS THE RIDGE PULLS TO THE E IN RESPONSE TO THE APPROACHING COLD FRONT THROUGH THU NIGHT...WINDS OVER THE NW WATERS WILL BECOME S-SW AT 15-20 KT AND BRIEFLY NW-N 15-20 KT BEHIND THE FRONT THU NIGHT INTO FRI MORNING BEFORE VEERING TO THE N-NE FRI AND NE-E SAT AND SUN...WITH WINDS E-SE 10-15 KT OVER THE WESTERN PORTION N OF 27N BY SUN AND MAINLY E 10-15 KT BY MON. E WINDS WILL BE HIGHER... IN THE RANGE OF 15-20 KT OVER THE FAR SOUTHERN WATERS NEAR EASTERN CUBA AND HISPANIOLA SUN AND MON. THE FRONT WILL REACH FROM NEAR 31N76W TO S FLORIDA EARLY FRI...EXTEND FROM 31N72W TO THE NW BAHAMAS TO S FLORIDA LATE FRI INTO SAT. THE FRONT WILL DISSIPATE OVER S FLORIDA BY LATE SAT WHILE ITS NORTHERN PORTION REACHES THE NE WATERS...THEN MOVES E OF AREA SUN. HIGH PRES WILL BUILD E OVER THE NORTHERN AND CENTRAL PORTIONS LATE SAT AND SUN AND BEGIN TO SHIFT E MON. CARIBBEAN AND TROPICAL N ATLC... BUOY OBSERVATIONS FROM EARLY THIS AFTERNOON SHOW MOSTLY E 15-20 KT WINDS OVER THE EASTERN CARIBBEAN N OF 16N...AND IN THE SW CARIBBEAN S OF 13N BETWEEN 75W AND 78W. OVER THE TROPICAL N ATLC ZONE...NE-E WINDS OF 20-25 KT ARE VERY PERSISTENT N OF 14N AS SEEN IN BUOY REPORTS. A COUPLE OF SHIP OBSERVATIONS FROM THIS MORNING AND EARLY AFTERNOON INDICATED SE WINDS OF 20-25 KT IN THE FAR NW PORTION OF THE CARIBBEAN N OF 15N AND W OF 84W. VIS SATELLITE IMAGERY HAS BEEN SHOWING VERY DENSE SMOKE ORIGINATING FROM HONDURAS AND THE YUCATAN PENINSULA STREAMING N AND NW ACROSS THE FAR NW CARIBBEAN SEA AND INTO MUCH OF THE CENTRAL GULF OF MEXICO REDUCING VISIBILITIES. WILL CONTINUE MENTION OF THESE WINDS FOR THIS FORECAST TIME PERIOD...MOST PROBABLY THROUGH THU NIGHT. MAX SEAS ARE ABOUT 8 FT IN THE SW CARIBBEAN...ABOUT 1 FT HIGHER THAN THE WAVEWATCH MODEL AND 7-9 FT IN THE NW SECTION NEAR THE COAST OF YUCATAN PENINSULA. SEAS UP TO 10 FT ARE EVIDENT IN THE TROPICAL N ATLC N OF ABOUT 14N...WHICH IS WHAT THE WAVEWATCH GUIDANCE DEPICTS. AS THE GULF OF MEXICO COLD FRONT APPROACHES THE NW CARIBBEAN FRI WINDS IN THE NW CARIBBEAN WILL DIMINISH. WINDS ELSEWHERE DIMINISH THU THROUGH SAT AS THE ATLC HIGH RETREATS EASTWARD. NEW HIGH PRES THAT BUILDS INTO THE NW ATLC SAT THROUGH MON THEN INCREASE THE GRADIENT SOME OVER THE N CENTRAL CARIBBEAN TO ALLOW FOR NE 20 KT TO KICK UP ALONG AND NEAR THE SOUTHERN PORTION OF HISPANIOLA AND NEAR THE COAST OF COLOMBIA. LIGHT E WINDS WILL TAKE HOLD OF THE TROPICAL N ATLC BEGINNING FRI THROUGH SUN WITH SEAS SUBSIDING THERE TO 6 FT. GULF OF MEXICO... PRELIMINARY 18 UTC SURFACE ANALYSIS SHOWS THE COLD FRONT NOW OVER EASTERN TEXAS PRECEDED BY A WIND SHIFT LINE. THE TEXAS COAST. THE BUOY ARRAY FROM ACROSS THE GULF SHOWS S TO SW WINDS OF 20-30 KT N OF 27N BETWEEN 85W AND 90W AND SE-S 20-25 KT ELSEWHERE OVER THE GULF E OF FRONT TO NEAR 84W. SEAS ARE MAXING OUT TO 10 FT N OF 27N BETWEEN 87W AND 90W AND TO 7 FT IN SW GULF. A STRONG RIDGE ALONG 27N WILL SHIFT EASTWARD THROUGH THU NIGHT IN ADVANCE THE COLD FRONT. MODELS ARE IN GOOD AGREEMENT WITH TIMING AND PROGRESSION OF FRONT REACHING FROM FLORIDA BIG BEND TO THE BAY OF CAMPECHE THU...THEN DISSIPATE FROM NAPLES FLORIDA TO THE YUCATAN CHANNEL FRI. THE CURRENTLY OBSERVED SLY WINDS WILL DIMINISH AS THEY BECOME MAINLY SW AHEAD OF THE FRONT. A NEW AREA OF HIGH PRES WILL THEN MOVE EASTWARD ACROSS THE NORTHERN WATERS FRI AND SAT...AND TO OVER THE FAR NE WATERS SUN AND MON ALLOWING FOR RETURN FLOW TO SET UP OVER THE FAR WESTERN GULF AS LOW PRES DEEPENS OVER THE SOUTHERN PLAINS STATES. THIS AREA OF LOW PRES WILL THEN DRIVE THE NEXT COLD FRONT TO OFF THE TEXAS COAST...AS LATEST MODELS HINT...OVERNIGHT ON SUN. EXPECT A WIND SHIFT OVER THE FAR WESTERN WATERS SUN NIGHT BEHIND THIS FRONT...POSSIBLY NW TO N 15-20 KT. WARNINGS.. ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE