000 AGXX40 KNHC 171833 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 245 PM EDT TUE MAY 17 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. GULF OF MEXICO... WEAK RIDGE DOMINATES THE WESTERN HALF OF THE GULF PRODUCING MAINLY N TO NE WINDS OF 10-15 KT. SEAS ARE BELOW 4 FT. A SERIES OF FRONTAL TROUGHS WILL CONTINUE TO MOVE S ACROSS THE MIDDLE AND EASTERN GULF THROUGH TONIGHT RESULTING IN W TO NW WINDS TO 20 KT MAINLY ACROSS THE N WATERS. HIGH PRES WILL ESTABLISH ITSELF OVER THE NW GULF TONIGHT AND DRIFT E INTO THE NE PORTION THU THEN E OF THE AREA THROUGH SAT. AS THIS WEATHER PATTERN EVOLVES... EXPECT INCREASING SLY RETURN FLOW OVER THE WESTERN HALF OF THE GULF WITH BUILDING SEAS TO 9 FT BY FRI. SE TO S WINDS WILL BLOW ACROSS THE ENTIRE GULF REGION BY SAT. FRESH TO STRONG RETURN FLOW IS EXPECTED IN THE EARLY MORNING HOURS OF FRI AND SAT AS A COLD FRONT SLOWLY MOVES THROUGH CENTRAL TX...INCREASING THE PRES GRADIENT. SW N ATLC... A COLD FRONT EXTENDING FROM 31N72W TO THE CENTRAL BAHAMAS WILL BECOME STATIONARY THIS AFTERNOON BEFORE WEAKENING AND LIFTING NORTHWARD WED INTO THU. SHOWERS AND TSTMS ARE NOTED ALONG AND AHEAD OF THE FRONT. S TO SW WINDS TO 20 KT CAN BE FOUND N OF 27N AND AHEAD OF THE FRONT TO 70W THROUGH WED NIGHT. A REINFORCING FRONTAL TROUGH WILL MOVE ACROSS THE NW PORTION OF THE AREA THROUGH WED. THE SUBTROPICAL RIDGE GRADUALLY BUILDS E ALONG 29N THU WITH MODERATE TO FRESH E TO SE WINDS S OF THE RIDGE...THEN WEAKENS AS IT MOVES TO 28N THROUGH SAT. A SURFACE TROUGH MAY DEVELOP E OF THE BAHAMAS LATE THU THROUGH SAT WHICH PREVENTS THE SUBTROPICAL RIDGE FROM BECOMING STRONG ENOUGH TO SUPPORT VIGOROUS TRADE WIND FLOW TO THE S. CARIBBEAN SEA AND THE TROPICAL N ATLANTIC ... A LOW AMPLITUDE TROPICAL WAVE CONTINUES TO MOVE WWD AND PRESENTLY EXTENDS ALONG 52W FROM 2N TO 9N. THE MOST RECENT WINDSAT PASS AND THE 1230 UTC ASCAT PASS SHOW THE WIND SHIFT ASSOCIATED WITH THIS WAVE AS WELL AS AN AREA OF NE WINDS TO 20 KT NEAR THE NORTHERN END OF THE WAVE AXIS DUE TO THE PRES GRADIENT BETWEEN THE TROPICAL WAVE AND A SURFACE RIDGE TO THE N. THE TROPICAL WAVE WILL PASS THROUGH FAR S WATERS OF THE TROPICAL N ATLC TONIGHT AND WED THEN MOVE INLAND ACROSS NORTHERN VENEZUELA LATE WED INTO THU. A SURFACE TROUGH PERSISTS OVER THE EASTERN CARIBBEAN NEAR 70W. AN EARLIER ASCAT PASS INDICATED THE WIND SHIFT ASSOCIATED WITH THIS TROUGH FORECAST TO REMAIN THERE THROUGH THU...THEN MOVE W AS THE SUBTROPICAL HIGH BUILDS TO THE N BEFORE DISSIPATING IN THE WESTERN CARIBBEAN FRI. E TO SE WINDS OF 10 TO 15 KT ARE NOTED E OF THE TROUGH AXIS WHERE SOME CONVECTION CONTINUES TO DEVELOP EACH DAY. WINDS ARE MAINLY LIGHT W OF THE TROUGH. A FRONTAL TROUGH IS STILL PRODUCING W TO NW WINDS OVER THE NW PORTION OF THE CARIBBEAN N OF 20N...INCLUDING THE YUCATAN CHANNEL. FRESH SE RETURN FLOW WILL LIE OVER THE GULF OF HONDURAS WED NIGHT THROUGH FRI. WARNINGS.. ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER GR