000 AGXX40 KNHC 230659 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 300 AM EDT FRI APR 23 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... SURFACE HIGH PRES 1015 MB CENTERED NEAR 27N84W CONTINUES TO DRIFT EAST WITH AN EXPANDING AREA OF SOUTHERLY RETURN COVERING MOST OF THE GULF W OF 90W WITH WINDS GENERALLY IN THE 15-20 KT RANGE. SEAS HAVE PICKED UP TO 5-7 FT ALONG THE TEXAS COAST. A 2336 UTC WINDSAT PASS CAPTURED SOME 20 KT WINDS ALONG THE W EDGE OF THE SWATH WHILE THE SUBSEQUENT 0232 UTC ASCAT PASS MISSED THE MAIN AREA OF CONCERN TONIGHT. SURFACE HIGH MOVES E INTO THE ATLC LATER TODAY WITH PRES GRADIENT STRENGTHENING FURTHER AS A COLD FRONT APPROACHES THE TEXAS COAST THIS EVENING WITH 20-25 KT WINDS OVER MOST AREAS W OF 85W TONIGHT. THE COLD FRONT WILL MOVE OFF THE TEXAS COAST EARLY SAT AND EXTEND FROM SE LOUISIANA TO NEAR VERACRUZ SAT EVENING. FRONT RAPIDLY WEAKENS TO A FRONTAL TROUGH FROM THE FL PANHANDLE TO SE BAY OF CAMPECHE LATE SUN AND EVENTUALLY MOVES INTO THE FAR SE GULF MON WHILE A WEAK TROUGH OF LOW PRES DEVELOPS OVER THE YUCATAN PENINSULA AND MOVES INTO THE BAY OF CAMPECHE TUE. CARIBBEAN SEA AND TROPICAL N ATLC FROM 07N TO 22N W OF 55W... A 0230 UTC ASCAT PASS INDICATED BRISK EASTERLY TRADES IN THE GULF OF HONDURAS AND AN AREA OF 15-20 KT TRADES OVER THE REMAINDER OF THE CARIBBEAN S OF 15N. AS HIGH PRES MOVES OUT OF THE GULF INTO THE ATLANTIC LATER TODAY...THE PRES GRADIENT IN THE CARIBBEAN SEA WILL TIGHTEN WITH EASTERLY TRADES INCREASING TO 20-25 KT OVER THE SW CARIBBEAN TONIGHT AND SAT WITH THE STRONGEST WINDS CONFINED TO THE COAST OF COLOMBIA. WINDS WILL ALSO CONTINUE IN THE GULF OF HONDURAS. THE DURATION AND LENGTHENING OF THE FETCH OF THESE STRONGER WINDS WILL ALSO RESULT IN SHORT PERIOD SEAS BUILDING TO 8-11 FT ACROSS THE SW PORTION OF THE BASIN. AS THE HIGH MOVES FURTHER E AND WEAKENS WINDS AND SEAS SUBSIDE OVER THE ENTIRE CARIBBEAN LATE SUN THROUGH TUE. IN THE TROPICAL N ATLC...A SERIES OF WEAK FRONTAL TROUGHS WILL MOVE ACROSS THE ZONE N OF 17N DURING THE NEXT SEVERAL DAYS. WINDS WILL SHIFT TO THE NE AT 10-15 KT BEHIND EACH OF THESE FEATURES. LONG PERIOD NW SWELL UP TO 10-11 FT WILL PROPAGATE INTO THE FAR NE PORTION OF THE ZONE SUN AND MON. S OF 17N...NE-E WINDS OF 10-15 KT WILL INCREASE TO 20 KT MON AND TUE AS THE PRES GRADIENT TIGHTENS. SW N ATLANTIC S OF 31N W OF 65W... THE LOW PRES AREA LOCATED JUST E OF THE ZONE HAS DISSIPATED LEAVING A NW TO SE ORIENTED TROUGH. A COLD FRONT CURRENTLY OVER THE FAR NE PORTION OF THE AREA CLEARS THE AREA BY MORNING WITH HIGH PRES EXPANDING OVER THE ENTIRE AREA LATER TODAY. A REINFORCING SURGE OF COLDER AIR AND STRONGER NW WINDS AT THE SURFACE SKIRTS THE FAR NE CORNER OF THE AREA LATE SAT AND SUN WITH SEAS OF 8-10 FT. THIS WILL BE SHORT LIVED AS THE AREA OF HIGH PRES MOVES E. SOUTHERLY RETURN FLOW WILL STRENGTHEN ALONG THE FLORIDA COAST SAT NIGHT THROUGH SUN AS THE HIGH PRES CENTER SHIFTS TO THE E AND AS THE NEXT COLD FRONT APPROACHES THE AREA. A LARGE AREA OF SW 20-25 KT...LOCALLY 30 KT WINDS SPREADS EWD MOST AREAS N OF 27N SUN NIGHT AND MON. THE COLD WILL TAKE ITS TIME EXITING THE SE COAST...FINALLY DOING SO LATE MON. THE FRONT WILL EXTEND FROM NEAR 31N74W TO SE FLORIDA EARLY TUE...AND FROM 31N68W TO JUST E OF THE CENTRAL BAHAMAS LATE TUE. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER COBB