000 AGXX40 KNHC 211823 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 230 PM EDT WED JUL 21 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 SURFACE TROUGH EXTENDS ALONG 28N93W 23N94W 18N93W. SCATTERED SHOWERS AND TSTMS ARE NOTED WITHIN ABOUT 120 NM EITHER SIDE OF TROUGH N OF 25N AND WITHIN 120 NM W OF TROUGH S OF 25N. VISIBLE SATELLITE IMAGERY SHOWS SOME CYCLONIC TURNING OVER THE SW PORTION OF THE GULF ASSOCIATED WITH THIS TROUGH WHICH IS FORECAST TO MOVE ACROSS THE WESTERN GULF THROUGH THU AND INLAND THU NIGHT. A RIDGE FROM NORTHERN FLORIDA TO LOUISIANA WILL PERSIST THROUGH FRI. E-SE WINDS OF 15-20 KT ARE BLOWING ACROSS THE STRAITS OF FLORIDA AND THE EASTERN GULF MAINLY S OF 27N E OF 88W. WINDS WILL DIMINISH ACROSS THE EASTERN GULF THU AS A HIGH PRES SETTLES OVER THE FLORIDA PANHANDLE...BUT COULD INCREASE AGAIN DURING THE UPCOMING WEEKEND AS A TROPICAL WAVE OR A LOW PRES POSSIBLY ENTERS THE EASTERN GULF SAT AND SUN. SE RETURN FLOW OF 20 KT IS EXPECTED IN THE NW PORTION OF THE GULF IN ABOUT 36 HOURS. CARIBBEAN SEA AND TROPICAL N ATLC... A TROPICAL WAVE IS OVER THE CENTRAL CARIBBEAN ALONG 76W WITH AXIS EXTENDING FROM EASTERN CUBA TO NORTHERN COLOMBIA. THE WAVE WILL MOVE THROUGH THE WESTERN CARIBBEAN THROUGH THU AND MOVE INTO THE YUCATAN PENINSULA FRI. ANOTHER TROPICAL WAVE CURRENTLY LOCATED ALONG 35W WILL MOVE INTO THE TROPICAL N ATLC WATERS FRI MORNING AND INTO THE E CARIBBEAN SEA SAT AND SUN. WINDS ARE EXPECTED TO INCREASE TO 20 KT ACROSS THE EASTERN CARIBBEAN MAINLY E OF 70W IN ABOUT 24 HOURS DUE TO THE PRES GRADIENT BETWEEN THE ATLC RIDGE AND THE DEVELOPING LOW PRES OVER THE CENTRAL BAHAMAS. E-SE WINDS TO 20 KT ARE N OF 19N W OF 60W IN THE TROPICAL N ATLC WATERS...AND OVER THE NW CARIBBEAN W OF 84W. OTHERWISE... LIGHTER THAN NORMAL TRADES ACROSS THE REMAINDER OF THE CARIBBEAN. WINDS AND SEAS WILL BE HIGHER NEAR SCATTERED SHOWERS AND TSTMS E OF 67W...INCLUDING THE LESSER ANTILLES AND COASTAL WATERS...AND OVER THE NW CARIBBEAN. SW N ATLC... A RIDGE...ANCHORED ON A 1028 MB HIGH NEAR THE AZORES...WILL REMAIN ALONG 31N THROUGH SUN. A SURFACE TROUGH EXTENDS FROM 24N67W TO DOMINICAN REPUBLIC NEAR 19N70W. SHIP AND BUOY OBSERVATIONS FROM THIS MORNING...AND AN ASCAT PASS FROM 1416 UTC INDICATED WINDS IN THE 20 TO 30 KT RANGE EITHER SIDE OF THE TROUGH AXIS S OF 25N BETWEEN 64W AND 73W. THE TROUGH WILL MOVE OVER THE SE BAHAMAS THIS EVENING THEN THROUGH THE REMAINDER OF THE BAHAMAS THROUGH THU NIGHT. A LOW... POSSIBLY DEVELOPING INTO A TROPICAL CYCLONE IS FORECAST ON THE WAVE NEAR 21N72W 1011 MB THIS EVENING...NEAR 22N74W THU MORNING...AND NEAR SE FLORIDA FRI MORNING. A TROPICAL DEPRESSION IS NOT EXPECTED TO FORM TODAY BUT ENVIRONMENTAL CONDITIONS ARE STILL FAVORABLE FOR SOME DEVELOPMENT AS THE SYSTEM MOVES TOWARD THE WEST-NORTHWEST AT ABOUT 10 MPH AWAY FROM HISPANIOLA INTO THE BAHAMAS ON THURSDAY. NOW...THERE IS A MEDIUM CHANCE OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ANOTHER SURFACE TROUGH IS OVER THE CENTRAL ATLC AND STRETCHES FROM 18N40W TO 30N41. THIS TROUGH...LIKELY THE NORTHERN PORTION OF THE TROPICAL WAVE LOCATED ALONG 35W...WILL CONTINUE TO MOVE WWD. E WINDS OF 15 KT ARE NOTED PER A 1234 UTC ASCAT PASS BEHIND THE TROUGH AXIS. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER GR