000 AGXX40 KNHC 071852 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 245 PM EDT FRI AUG 07 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... WEAK RIDGE REMAINS IN TRACT ACROSS THE NORTHERN GULF EARLY THIS AFTERNOON. BOTH BUOY OBSERVATIONS AND A QUIKSCAT PASS FROM JUST PASSED 1200 UTC THIS MORNING SHOWED LIGHT WINDS WITH THE BUOYS REPORTING SEAS OF 1-2 FT. THESE SEASTATE CONDITIONS REMAIN IN PRETTY GOOD AGREEMENT WITH THE NOAA WAVEWATCH MODEL INITIALIZED AT 1200 UTC THIS MORNING. OTHERWISE...A SURFACE TROUGH EXTENDS FROM 24N89W NE TO APALACHEE BAY MOVING NW ABOUT 10 KT. THE MAIN ISSUE WITH THE TROUGH CONTINUES TO BE THE DEVELOPMENT OF SCATTERED TSTM ACTIVITY WITHIN 60 NM OF THE TROUGH N OF 26N. THE TROUGH IS FORECAST TO DISSIPATE NEAR SE LOUISIANA COAST LATE TONIGHT INTO SAT MORNING. BOTH THE GLOBAL MODELS AND THE REGIONAL NAM GUIDANCE ARE IN VERY GOOD AGREEMENT THAT THE RIDGE WILL HOLD ACROSS THE NORTHERN GULF THROUGH EARLY NEXT WEEK WITH LITTLE OVERALL CHANGE IN PRESENT OBSERVED CONDITIONS. THE ONLY UNCERTAINTY IN THE LONG RANGE OF THIS FORECAST PACKAGE IS WHETHER THE NORTHERN PORTION OF CARIBBEAN TROPICAL WAVE CURRENTLY ALONG 71W MOVES INTO THE FAR SE GULF WATERS. MODELS...FOR THE MOST PART...ARE VERY LOW KEY WITH THIS SCENARIO IN SHOWING A SLIGHT WIND SHIFT OVER THE FAR SE GULF LATE TUE INTO WED. FOR THIS FORECAST WILL STATE TROPICAL WAVE MAY ENTER THE SE GULF AT THAT TIME...AND WAIT TO SEE HOW FUTURE MODEL GUIDANCE HANDLES THIS FEATURE. TROPICAL ATLC AND CARIBBEAN SEA... A TROPICAL WAVE HAS MOVED W INTO THE EASTERN PORTION OF THE YUCATAN PENINSULA. THE NEXT TROPICAL WAVE IS CURRENTLY ALONG 70W MOVING W 15 KT. WITH THE WAVE BEING UNDER A NARROW UPPER TROUGH...SCATTERED TSTMS HAVE FIRED UP WITHIN 120 NM W OF THE WAVE FROM 14N-16N. THE WAVE WILL MOVE ACROSS THE REMAINDER OF THE CENTRAL CARIBBEAN SEA THROUGH TONIGHT...THEN ACROSS THE WESTERN DURING THE WEEKEND...EXITING THE AREA MON. ANOTHER TROPICAL WAVE IN THE CENTRAL IS ALONG 53W MOVING W ABOUT 17 KT. A SURFACE TROUGH IS WITHIN 360-450 NM E OF THE WAVE. GLOBAL MODELS ARE RATHER PERSISTENT IN HINTING OF SOME FORM OF A LOW FORMING ALONG THE TROUGH AND TRACKING WNW TO NEAR 16N55W BY SUN AFTERNOON...THEN INTO THE FAR NE CARIBBEAN SEA AND FAR NW PORTION OF THE TROPICAL N ATLC AND FAR SE POTION OF THE SW N ATLC NEXT WEEK. THERE STILL REMAINS UNCERTAINTY WITH JUST HOW REALISTIC THE MODELS ARE WITH BUILDING UP THIS WAVE TO BECOME A LOW AS CONDITIONS ALOFT REMAIN VERY HOSTILE. TRADES WILL CONTINUE IN THE 20-25 KT RANGE OVER MUCH OF THE CENTRAL CARIBBEAN...WITH THE POSSIBILITY OF 25-30 KT WINDS OVER A SMALL AREA ALONG THE COAST OF COLOMBIA THROUGH SUN MORNING. HOWEVER...THESE WINDS SHOULD BE SHORT-LIVED. LATEST WAVEWATCH BUILDS SEAS NEAR THE COAST OF COLOMBIA TO 13 FT DURING THE WEEKEND...AND THEN DROPS THEM QUITE RAPIDLY EARLY NEXT WEEK TO ABOUT 8 OR 9 FT AS GRADIENT RELAXES OVER JUST ABOUT THE ENTIRE CARIBBEAN. THIS APPEARS REASONABLE AT THE PRESENT TIME. SW ATLC W OF 55W... A RIDGE EXTENDING FROM 30N65W TO CENTRAL FLORIDA CONTINUES TO BE THE DOMINANT FEATURE OF THE AREA MAINTAINING GENERALLY LIGHT CONDITIONS AS SEEN IN BUOY AND SHIP OBSERVATIONS FROM THIS MORNING AND EARLY AFTERNOON. A QUIKSCAT PASS FROM NEAR 1030 UTC THIS MORNING ALSO REVEALED SIMILAR CONDITIONS WITH THE EXCEPTION BEING THE FAR SOUTHERN WATERS E OF THE BAHAMAS WHERE E-SE WINDS WERE IN THE 15-20 KT RANGE. THE RIDGE IS FORECAST TO WEAKEN THROUGH SUN AS A SURFACE FROM THE SE BAHAMAS TO 30N72W MOVES NW THROUGH SAT. THE TROUGH THEN BECOMES DIFFUSE OVER THE NW PORTION NEAR THE NW BAHAMAS SUN. TSTMS HAVE AGAIN BECOME ACTIVE ALONG...AND WITHIN 90-100 OF THE TROUGH. GUSTY WINDS CAN BE EXPECTED WITH THIS ACTIVITY. SEAS OF 4-6 FT WILL EXIST E OF THE BAHAMAS...AND 3 TO 5 FT W OF THE BAHAMAS. WAVEWATCH GUIDANCE DELAYS BUILDING SEAS E OF THE BAHAMAS TO 7 OR 8 FT IN E SWELL E OF THE BAHAMAS TILL LATE WED. WAVE FEATURE OR WEAK LOW MENTIONED ABOVE THEN ENTERS THE FAR SE PART OF THE SW ATLC BEGINNING MON NIGHT INTO TUE...THEN TO NEAR THE SE BAHAMAS WED...ALL OF THIS WITH UNCERTAINTY ON JUST HOW FAR N THE WAVE WILL EXTEND...AND AS TO WHETHER A DEFINITIVE LOW FEATURE DEVELOPS FROM IT OR NOT. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. $$ FORECASTER AGUIRRE