000 AGXX40 KNHC 091851 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 300 PM EDT FRI APR 9 2004 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. SW N ATLC WATERS... AT THE UPPER LEVELS...SHORTWAVE TROUGH THAT ENTERED THE AREA LAST NIGHT HAS QUICKLY MOVED E OF 65W. BEHIND IT ZONAL FLOW HAS SET UP AGAIN IN ADVANCE OF HIGH PRES RIDGING BUILDING E ACROSS THE AREA FROM THE GULF OF MEXICO. UPPER FLOW WILL BECOME SW OVER THE W SECTION TUE AND WED IN ADVANCE OF SHARP AND RATHER STRONG DEEP-LAYER TROUGH MOVING ACROSS THE GULF OF MEXICO. AT THE SURFACE...WEAK COLD FRONT OVER THE NW PORTION WILL EXTEND FROM 31N75W TO 28N80W BY EARLY THIS EVENING...AND ALONG 25N E OF 74W BY SAT NIGHT. LIGHT NW-N WINDS WILL FOLLOW BEHIND THE FRONT. E OF THE FRONT HIGH PRES WILL MAINTAIN A LIGHT WIND REGIME THROUGH AT LEAST SAT NIGHT THEN MOVE E MON AS LOW PRES OVER THE GULF OF MEXICO MOVES NE INTO THE SE U.S. SLY WINDS WILL INCREASE N OF 27N MON AND TUE WITH BUILDING SEAS. COLD FRONT ASSOCIATED WITH THE GULF OF MEXICO LOW WILL BE MORE SIGNIFICANT THAN THE ONE CURRENTLY AFFECTING THE SW N ATLC WATERS. MODELS SUGGEST PRES GRADIENT WILL TIGHTEN AHEAD OF THE GULF OF MEXICO COLD FRONT BEFORE MOVING OFF THE GEORGIA AND NE FLORIDA COAST TUE. SQUEEZE PLAY INTERACTION BETWEEN LOW PRES OVER THE SE U.S. AND HIGH PRES RIDGING OVER THE ATLC WILL ALLOW FOR SLY WINDS TO INCREASE. GFS INDICATES SPEEDS UP TO 30 KT AHEAD OF THE FRONT ON MON. I THINK IT MAY BE TOO HIGH FOR NOW SO WILL CONTINUE WITH MENTION OF 20-25 KT SLY WINDS AHEAD OF THE FRONT. MAY ADD THE TERM GUSTY AT A LATER TIME IF I FEEL THAT WINDS MAY SURPASS THE 25 KT THRESHOLD. GULF OF MEXICO... AT THE UPPER LEVELS...SHORTWAVE TROUGH MOVING RAPIDLY ACROSS THE NORTH/CENTRAL GULF WILL MOVE ACROSS FLORIDA TONIGHT. ELSEWHERE... MID/UPPER LEVEL RIDGING DOMINATES THE AREA. AMPLE UPPER LEVEL MOISTURE IS NOTED STREAMING NE FROM THE PACIFIC ACROSS MEXICO AND INTO THE SE OF LINE 24N98W 27N90W TO FLORIDA BIG BEND. ONLY WIDELY SCATTERED TSTMS HAVE BEEN NOTED OVER THE E GULF SECTION EARLY THIS AFTERNOON. THIS MID/UPPER FLOW WILL CONTINUE THROUGH SUNDAY WITH NEXT SHORTWAVE TROUGH...ASSOCIATED WITH COLD FRONT MENTIONED ABOVE UNDER SW N ATLC...MOVING INTO THE W GULF SUNDAY AND MON THEN SHARPING TUE OVER THE CENTRAL GULF AND EXITING THE GULF LATE WED. AT THE SURFACE...WEAKENING SURFACE TROUGH FROM NEAR FORT MYERS FLORIDA SW ALONG 24N86W TO NW YUCATAN PENINSULA WILL SLOWLY MOVE E AND GRADUALLY DISSIPATE BY SAT NIGHT. LIGHT NE TO E WINDS ARE NOTED N OF THE TROUGH...AND LIGHT SLY WINDS S OF THE TROUGH WITH SEAS 2-3 FT ACROSS THE ENTIRE GULF. THESE LIGHT WINDS AND LOW SEAS WILL PREVAIL THROUGH EARLY SAT NIGHT AT WHICH TIME THE NEXT COLD FRONT IS EXPECTED TO MOVE OFF THE TEXAS COAST. RIGHT NOW IT APPEARS THAT IT MOVE OFF THE COAST AT THIS TIME...BUT POSSIBLY BE LATER THAT NIGHT OR EARLY SUN MORNING. SHIFTING WINDS TO THE N IN THE 20-25 KT RANGE WILL FOLLOW BEHIND THE FRONT WITH HIGHER GUSTS PRIMARILY OVER THE SW SECTION (ZONE 082). THIS ALL DEPENDS ON WHETHER LOW PRES FORMS...AND HOW FAR IT FORMS ALONG FRONT WHICH WILL AFFECT MAGNITUDE OF TIGHTENING OF THE PRES GRADIENT. THIS IS THE SAME LOW MENTIONED ABOVE UNDER SW N ATLC WATERS. CARIBBEAN AND TROPICAL ATLANTIC... BELOW NORMAL ELY TRADE WINDS WITH 20 KT CONTINUING ALONG COLOMBIAN COAST...AND OVER E CARIBBEAN (ZONE 086) S OF 14N. THESE TRADES WILL CONTINUE THROUGH WED. STILL APPEARS THAT WINDS MAY VEER MORE TO THE S AND INCREASE OVER THE NW PORTION OF THE CARIBBEAN (ZONE 082) MON THEN WEAKEN TUE IN ADVANCE OF THE NEXT COLD FRONT DESCRIBED IN ABOVE PARAGRAPHS. THE COLD FRONT WILL ENTER THE NW CARIBBEAN LATE MON OR EARLY TUE MORNING FOLLOWED BY MODERATE TO STRONG N WINDS AND BUILDING SEAS IN NLY SWELLS...ESPECIALLY NEAR W CUBA AND THE YUCATAN CHANNEL. OTHERWISE LIGHT WINDS UNDER A WEAK PRES PATTERN WILL CONTINUE ACROSS THE AREA THROUGH THE PERIOD. WARNINGS...NONE. FORECASTER AGUIRRE