000 AGXX40 KNHC 181846 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 245 PM EDT WED AUG 18 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 TROUGH OF LOW PRES...THE REMNANTS OF A TROPICAL WAVE...IS IN THE SW GULF AND BAY OF CAMPECHE. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING OUT AHEAD OF THE TROUGH. THE TROUGH WILL MOVE INLAND OVER MEXICO TONIGHT. SCATTERED SHOWERS AND TSTMS ARE MOVING INTO THE FAR SE GULF FROM THE STRAITS OF FLORIDA OUT AHEAD OF A TROPICAL WAVE THAT IS CURRENTLY OVER CUBA. THIS ACTIVITY WILL CONTINUE TO SPREAD INTO THE GULF AS THE WAVE MOVES CLOSER. A RIDGE OF HIGH PRES EXTENDING ACROSS FLORIDA FROM THE ATLC IS DRAPED ACROSS THE GULF ALONG 25N. THE RIDGE WILL LIFT TO THE N TO ALONG 27N FRI AS THE TROPICAL WAVE CURRENTLY IN THE NW CARIBBEAN SEA AND SW N ATLC MENTIONED ABOVE APPROACHES THE SOUTHERN GULF. THE TROPICAL WAVE WILL ENTER THE S CENTRAL GULF MOVING THROUGH THE YUCATAN CHANNEL LATE THU NIGHT INTO EARLY FRI EVENTUALLY DISSIPATING OVER THE SW GULF NEAR EASTERN MEXICO ON SAT. A NEW HIGH PRES CENTER WILL DEVELOP OVER THE SE GULF LATE FRI NIGHT SHIFTING TO THE CENTRAL GULF NEAR 25N87W SAT NIGHT THEN SHIFTS TO THE NW GULF ON SUN. THE 12Z RUN OF THE GFS NOW DROPS DOWN A COLD FRONT AND AREA OF LOW PRES IN THE N CENTRAL GULF SE OF LOUISIANA SUN NIGHT LINGERING JUST OFFSHORE THROUGH MON. PREVIOUS MODEL RUNS DID NOT INDICATE THIS SCENARIO WHILE THE ECMWF DOES NOT DEVELOP A LOW BUT DOES DROP EITHER A FRONT OR FRONTAL TROUGH INTO THE SAME AREA BY MON. WILL CARRY A FRONTAL TROUGH FOR NOW IN THE FCST. SW N ATLC... A NEARLY STATIONARY FRONTAL TROUGH IS IN THE NW PORTION WITH SCATTERED SHOWERS AND ISOLATED TSTMS FIRING UP ALONG EITHER SIDE OF THE BOUNDARY. THIS FEATURE MAY LINGER IN THE NW PORTION THROUGH THE END OF THE WEEK WITH MAINLY LIGHT WINDS OCCURRING IN THE VICINITY OF THE FEATURE. THE NORTHERN PORTION OF A TROPICAL WAVE EXTENDS FROM THE CENTRAL BAHAMAS TO EASTERN CUBA. A SURGE OF EASTERLY WINDS ALONG WITH SCATTERED SHOWERS AND TSTMS IN SQUALLS ASSOCIATED WITH THE WAVE ARE OCCURRING OVER THE SOUTHERN PORTION. THIS WAVE WILL MOVE THROUGH THE STRAITS OF FLORIDA LATE TONIGHT INTO EARLY THU MOVING W OF THE AREA LATER THU. A TROUGH IS OVER THE FAR E PORTION EXTENDING FROM NEAR 30N55W TO 25N58W WITH SCATTERED SHOWERS OCCURRING ALONG THE FEATURE. THE TROUGH WILL DRIFT TO THE W MOVING TO ALONG 65W BY EARLY FRI DISSIPATING BY SAT AS HIGH PRES BUILDS IN FROM THE W. OTHERWISE 1020 MB HIGH PRES IS CENTERED NEAR 28N66W WITH WEAK RIDGING EXTENDING TO THE NW BAHAMAS. THE HIGH CENTER WILL MOVE TO JUST NE OF THE CENTRAL BAHAMAS EARLY FRI AS THE TROUGH MOVES TO THE W THEN WILL DISSIPATE SAT AS THE ABOVE MENTIONED CENTRAL ATLC RIDGING BUILDS WESTWARD AND OVERTAKES THE HIGH. THE RIDGE WILL BECOME ESTABLISHED ALONG 28N BY EARLY SUN THEN WILL LIFT N TO ALONG 29N/30N BY EARLY NEXT WEEK AS A TROPICAL WAVE APPROACHES THE FAR SE PORTION FROM THE TROPICAL N ATLC WATERS BY LATE MON. CARIBBEAN SEA AND TROPICAL N ATLC... A STRONG TROPICAL WAVE HAS PUSHED INTO THE NW CARIBBEAN EXTENDING FROM EASTERN CUBA TO WESTERN JAMAICA TO NEAR 12N78W IN THE SW CARIBBEAN. NUMEROUS SHOWERS AND SCATTERED TSTMS EXIST ACROSS THE CENTRAL CARIBBEAN AND ARE NOW ADVANCING INTO THE W CARIBBEAN ALONG WITH THE WAVE. E-SE WINDS TO 20 KT ARE OCCURRING IN THE WAKE OF THE WAVE OVER THE CENTRAL AND E CARIBBEAN W OF 64W AS CAPTURED BY A RECENT 15Z ASCAT PASS WITH WINDS LOCALLY TO 25 KT. EXPECT HIGHER WINDS AND SEAS TO OCCUR IN SQUALLS NEAR THE WAVE AXIS MAINLY IN THE NW CARIBBEAN. THE WAVE WILL REACH TO ALONG 80W BY LATE TONIGHT/EARLY THU MOVING INLAND OVER THE YUCATAN PENINSULA EARLY FRI. WINDS AND SEAS WILL BEGIN TO DIMINISH AND SUBSIDE THIS WEEKEND OVER THE W CARIBBEAN AS THE WAVE MOVES NW OF THE AREA. EASTERLY TRADES WILL INCREASE BACK TO 20 KT IN THE CENTRAL CARIBBEAN SAT NIGHT THROUGH MON AS THE PRES GRADIENT INCREASES DUE TO BUILDING ATLC RIDGING NE OF THE LEEWARD ISLANDS. IN THE TROPICAL N ATLC...NE-E WINDS OF 10-15 KT DOMINATE THE REGION WITH HIGH PRES LOCATED NW OF THE WATERS. A WEAK TROUGH WILL MOVE THROUGH THE FAR SOUTHERN PORTION THU AND THU NIGHT WITH SCATTERED SHOWERS OCCURRING ALONG IT. ANOTHER TROUGH WILL SKIRT ACROSS THE NORTHERN PORTION THU THROUGH FRI MOVING NW OF THE AREA SAT. A TROPICAL WAVE WILL APPROACH 55W LATE SUN INTO MON. ALL EYES WILL BE FOCUSED A SECOND TROPICAL WAVE WHICH MAY BECOME QUITE VIGOROUS WITH POSSIBLE LOW PRES DEVELOPING ALONG IT BY THE MIDDLE PART OF NEXT WEEK. THE GFS MODEL SOLUTION CONTINUES TO BE MUCH STRONGER THAN THE ECMWF SOLUTION. WARNINGS... SW N ATLC... .NONE. CARIBBEAN... .NONE. .GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER LEWITSKY