000 AGXX40 KNHC 181746 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 145 PM EDT SAT JUN 18 2005 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... UNSEASONABLY SHARP MID TO UPPER LEVEL TROUGH HAS DRAGGED A COLD FRONT INTO THE FAR NE CORNER OF THE GULF OF MEXICO FROM APALACHICOLA FLORIDA TO NEW ORLEANS LOUISIANA. W/NW WINDS HAVE SHIFTED TO THE N OVER THE COASTAL WATERS IN THOSE AREAS. THIS SHARP UPPER LEVEL TROUGH COMBINED WITH CONVECTIVE FEEDBACK PROBLEMS HAS WREAKED HAVOC ON THE PERFORMANCE OF THE GFS AND HENCE ITS RELIABILITY IN THIS FORECAST. FOR OPENERS THE GFS IS FORECASTING TWO AREAS OF LOW PRESSURE BEGINNING TOMORROW NIGHT OVER THE SE HALF OF THE GULF WITH ONE LOW FORECAST TO MOVE ACROSS FLORIDA ALONG THE SOUTHWARD PROGRESSING FRONTAL TROUGH AND THE OTHER TO REMAIN IN THE BAY OF CAMPECHE WITH A SPIN-OFF FEATURE PIVOTING AROUND THIS LOW ACROSS THE N-CENTRAL GULF MON NIGHT INTO TUE. THE RESULTANT WIND FIELDS LOOK UNREALISTIC AND THEREFORE HAVE OPTED TOTALLY OUT OF THE GFS SOLUTION AND LEANED TOWARD THE NAM/NOGAPS SOLUTIONS WHICH ESSENTIALLY KEEP LIGHT...BUT SHIFTING WINDS OVER THE NORTHERN GULF IN THE VICINITY OF THE SOUTHWARD PROGRESSING...BUT WEAKENING FRONTAL TROUGH IN THE NE GULF. NAM/NOGAPS ARE FORECASTING 10-15 KT WINDS...INCREASING TO LOCALLY 20 KT TUE AND WED OVER THE BAY OF CAMPECHE IN ASSOCIATION WITH A QUASI-STATIONARY TROUGH OVER THE AREA. SW N ATLC... WEAK ATLC RIDGE ANCHORED BETWEEN A SW-NE ORIENTED SURFACE TROUGH FROM HISPANIOLA THROUGH 31N60W AND A COLD FRONT OVER THE FAR NW PORTION OF THE AREA. RIDGE EXPECTED TO REMAIN WEAK THROUGH THE SHORT TERM PERIOD. FOR REASONS MENTIONED IN THE PREVIOUS SECTION HAVE DECIDED TO DISCOUNT THE GFS SOLUTION OF A LOW MOVING NEWD FROM FLORIDA ON MON AND ACROSS THE NW PORTION OF THE AREA MON NIGHT AND TUE MORNING AND LEAN TOWARD THE NAM WHICH FORECASTS SWLY WINDS AHEAD OF THE FRONTAL TROUGH. INTERESTINGLY ENOUGH THE NOGAPS HAS A SIMILAR SOLUTION TO THE GFS...ALTHOUGH THE SURFACE LOW IS WEAKER AND MORE PROGRESSIVE. OUTLOOK...LIGHT WINDS CONTINUE AS WEAK ATLC RIDGE PERSISTS WITH THE EXCEPTION OF 15 KT ELY WINDS OVER AREAS S OF 23N. CARIBBEAN AND TROPICAL ATLC... TROPICAL WAVES ARE NOTED ALONG 63W AND 83W MOVING WWD 10-15 KT. ATLC RIDGE N OF THE AREA SHOULD MAINTAIN STEADY EASTERLIES ACROSS THE AREA. CURRENT WINDS 0F 20-25 KT MOST AREAS E OF 80W WILL INCREASE FURTHER TO SOLID 25 KT OVER THE SW/CENTRAL CARIBBEAN SUN NIGHT THROUGH MON NIGHT. GFS PAINTS A FEW 30 KT BARBS OVER FAVORED FUNNELING AREAS ALONG THE COAST OF COLOMBIA...HOWEVER AS NOTED PREVIOUSLY WILL ONLY MAX OUT WINDS AT 25 KT GIVEN THAT WE ARE A MONTH SHY FROM THE CLIMATOLOGICAL PEAK OF THESE WINDS AND THE RELATIVE WEAKNESS OF THE ATLC RIDGE TO THE N. OUTLOOK...ATLC RIDGE REMAINS RELATIVELY WEAK AND OVERALL PRESSURE PATTERN WEAKENS...EXPECT EASTERLY TRADES TO DROP OFF TO 15-20 KT MOST AREAS. WARNINGS... ATLANTIC NONE. CARIBBEAN NONE. GULF OF MEXICO NONE. FORECASTER COBB