000 AGXX40 KNHC 281756 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 215 PM EDT WED JUL 28 2010 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... A 1021 MB HIGH LOCATED NEAR 28N88W WITH A RIDGE W TO THE NE TEXAS COAST WILL MOVE TO THE NW PORTION OF THE GULF FRI AS A FRONTAL TROUGH CLIPS THE FAR NE PART FRI THROUGH SUN. LAND-BASED STATIONS AND BUOY OBSERVATIONS ARE CURRENTLY SHOWING WINDS FROM A GENERAL E-SE DIRECTION OVER A WIDE SWATH OF THE GULF WATERS WITH SEAS IN THE 3 TO 5 FT RANGE ACROSS MOST OF THE AREA. THE EXCEPTIONS ARE THE FAR NW PORTION PARTICULARLY N OF 25N AND W OF 94W WHERE SE WINDS OF 20 KT ARE BLOWING...AND FROM 21N TO 24N BETWEEN 90W AND 94W WHERE THE FLOW IS FROM THE E TO SE AT 20 KT. WINDS WILL REMAIN ON THE LIGHT SIDE ALONG WITH LOW SEA STATE VALUES DURING MOST OF THE FORECAST PERIOD AS THE SURFACE HIGH SETTLES OVER THE NW PORTION OF THE GULF FRI THROUGH SUN. SW N ATLC... A WEAKENING FRONTAL BOUNDARY IS CLIPPING THE FAR NE PORTION OF THE AREA PRODUCING SOME SHOWER ACTIVITY AND GUSTY WINDS. A 1019 MB HIGH IS CENTERED OVER THE NW BAHAMAS WITH A RIDGE WESTWARD TO ACROSS FLORIDA AND INTO THE GULF OF MEXICO 1021 MB HIGH. S OF THE RIDGE WINDS ARE E-SE 10-15 KT W OF BAHAMAS AND NE-E 10-15 KT TO THE E BAHAMAS. AN EARLIER ASCAT PASS INDICATED SLIGHTLY HIGHER WINDS NEAR THE WINDWARD PASSAGE. ACCORDING TO THE COMPUTER MODELS...THE RIDGE WILL BEGIN TO RETREAT EASTWARD FRI THROUGH SUN IN RESPONSE TO A FRONTAL TROUGH THAT SLOWLY SAGS SOUTHEASTWARD ACROSS THE SE UNITED STATES FRI THROUGH SUN. WINDS OVER THE NORTHERN WATERS ARE FORECAST TO BECOME SW TO W 10-15 KT OCCASIONALLY 20 KT E OF 75W BY SAT. EXPECT ALSO OCCASIONALLY 20 KT WINDS S OF 22N MAINLY DURING THE EVENING HOURS TONIGHT AND THU. WINDS WILL INCREASE TO 20 KT ACROSS THE SE PART LATE SAT DUE TO THE PRESENCE OF A TROPICAL WAVE MOVING ACROSS THE CARIBBEAN SEA. CARIBBEAN SEA AND TROPICAL N ATLC... A RECENT WINDSAT PASS SHOWED NE TO E WINDS OF 20 TO 25 KT OVER THE EASTERN CARIBBEAN AHEAD OF THE TROPICAL WAVE LOCATED ALONG 63W/64W. IN THE NW CARIBBEAN ZONE...E-SE WINDS OF 20-25 KT ARE CONFINED S OF 18N W OF 85W AS NOTED IN AN EARLIER ASCAT PASS. WINDS AND SEAS ARE EXPECTED TO DIMINISH ACROSS THE CENTRAL CARIBBEAN FRI...BUT WILL INCREASE AGAIN ACROSS THE EASTERN CARIBBEAN LATE FRI WITH THE APPROACHING TROPICAL WAVE. SEE BELOW FOR MORE DETAILS. THE TROPICAL WAVE OVER THE EASTERN CARIBBEAN WILL REACH THE CENTRAL CARIBBEAN THU AND THU NIGHT...AND MOVE ACROSS THE WESTERN PORTION FRI AND SAT TO W OF THE AREA LATE SAT INTO SUN. PRESENTLY...SCATTERED SHOWERS AND ISOLATED TSTMS ARE NEAR THE WAVE AXIS. ANOTHER TROPICAL WAVE...WITH BROAD CYCLONIC FLOW ABOUT THE WAVE AXIS...IS WELL E OF THE AREA OVER THE CENTRAL ATLANTIC. THIS WAVE IS FORECAST TO ENTER THE EASTERN SECTION OF THE TROPICAL N ATLC ZONE THU...AND MOVE THROUGH THE REMAINDER OF THAT ZONE THROUGHOUT THU BEFORE ENTERING THE EASTERN CARIBBEAN SEA LATE FRI AND SAT...AND THE CENTRAL CARIBBEAN SUN. A WINDSAT PASS FROM EARLY THIS MORNING INDICATED A BROAD AREA OF NE WINDS OF 20 TO 25 KT FROM 14N TO 23N E OF 50W DUE TO THE PRES GRADIENT BETWEEN THE WAVE AND THE ATLC RIDGE ANCHORED ON A 1025 MB HIGH NEAR 30N42W. THIS FLOW IS ALLOWING SEAS TO BUILD TO AROUND 10 FT NEAR THE NORTHERN END OF THE WAVE AXIS. THESE MARINE CONDITIONS WILL BEGIN TO AFFECT THE TROPICAL N ATLC TONIGHT AND CONTINUE THROUGH THU REACHING THE CARIBBEAN SEA FRI AND SAT...THEN SHIFT TO THE N CENTRAL CARIBBEAN SUN IN TANDEM WITH THE WAVE. WARNINGS... SW N ATLC... .NONE. CARIBBEAN... .NONE. .GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER GR