000 AGXX40 KNHC 170737 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 330 AM EDT SAT JUL 17 2010 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... LATEST BUOY OBSERVATIONS FROM ACROSS THE AREA CONTINUE TO SHOW RATHER LIGHT WINDS...WITH RANGES OF 5-10 KT IN THE WESTERN PORTION ...10-15 KT RANGE IN THE MIDDLE AND EASTERN WITH THE EXCEPTION OF THE FAR SE PORTION WHERE WINDS ARE HIGHER...IN THE 15-20 KT CLOSE AND THROUGH THE STRAITS OF FLORIDA. WIND DIRECTION IS GENERALLY E-SE...EXCEPT IN THE SW ZONE WHERE WINDS ARE MAINLY NE-E. THE OBSERVATIONS REPORT SEA HEIGHTS IN THE 3-4 FT RANGE IN THE EASTERN GULF WITH SEAS HIGHER NEAR THE STRAITS OF FLORIDA ...MAXING OUT AT 5-7 FT THERE. W OF 90W...SEAS ARE RANGING FROM 1-3 FT. THE MAIN OF INTEREST CONTINUES TO BE PROGRESSIVE TROUGH THAT HAS NOW ENTERED THE WESTERN PORTION ALONG 91W MOVING W ABOUT 10 KT. BUOY OBSERVATIONS IN THE VICINITY OF THE TROUGH HAVE SHOWN AND ARE CURRENTLY REVEALING A WIND SHIFT FROM NE-E AHEAD OF THE TROUGH TO SE BEHIND IT. MINIMAL SHOWER AND TSTMS ACTIVITY IS ASSOCIATED WITH THE TROUGH AS OBSERVED ON SATELLITE IMAGERY. LATEST MODEL RUNS ARE IN GOOD AGREEMENT THAT THE TROUGH THEN BECOMES DIFFUSE AS IT APPROACHES THE TEXAS COAST EARLY THIS EVENING. THE 0O UTC RUN OF THE REGIONAL NAM MODEL HAS COME MORE IN LINE WITH THE GLOBAL MODELS IN KEEPING THE FEATURE WEAK AS IT APPROACHES THE COAST BEFORE BECOMING DIFFUSE AS OPPOSED TO YESTERDAY WHEN IT WAS SHOWING A CLOSED LOW APPROACHING THE COAST. THE PRELIMINARY 0600 SURFACE ANALYSIS SHOWS A WEAK RIDGE EXTENDING FROM CENTRAL FLORIDA TO NEAR 26N88W. AS THE TROUGH PULLS TO THE W...THE RIDGE WILL THEN LIFT N TO NEAR 31N BEGINNING SUN NIGHT AND REMAIN THERE BY DAY 5 (WED). HOWEVER...LITTLE IF NO RESPITE IN THE CURRENT E-SE 15-20 KT WINDS OVER THE SE PORTION S OF 25N WILL BE SEEN AS ANOTHER TROUGH MOVES INTO THE FAR SE PORTION LATE MON...THEN MOVE THROUGH THE REST OF THE E GULF S OF ABOUT THROUGH LATE MON...AND INTO MIDDLE GULF TO NEAR 89W BY TUE AFTERNOON. BY LATE WED...THE TROUGH SHOULD BE OVER THE WESTERN GULF NEAR 92W BRINGING ANOTHER SURGE OF E-SE 15-20 KT WINDS IN ITS WAKE DUE TO THE PRES DIFFERENCE BETWEEN ATLC RIDGING NE OF THE AREA AND THE TROUGH. CARIBBEAN SEA AND TROPICAL N ATLC... UNSETTLED WEATHER CONTINUES OVER MUCH OF THE WESTERN AND CENTRAL CARIBBEAN ZONES UNDER BROAD LOW PRES DUE TO THE COMBINATION OF A SURFACE TROUGH ROUGHLY FROM 10N81W TO A 1011 MB LOW NEAR 14N83W AND NW TO 20N86W...AND AN UPPER LEVEL LOW OVER THE STRAITS OF FLORIDA. A TROPICAL IS ALONG 72W S OF 19N MOVING W 10 KT. LATEST SATELLITE IMAGERY SHOWS ABUNDANT DEEP ATMOSPHERIC MOISTURE SUSTAINING NUMEROUS SHOWERS AND CLUSTERS OF TSTMS TO EXIST THROUGHOUT THE ENTIRE CARIBBEAN SEA AND WESTERN PORTION OF THE TROPICAL N ATLC ZONE. THE WAVE IS PROJECTED TO REACH NEAR 76W EARLY THIS EVENING...THEN TO NEAR 80W SUN EVENING BEFORE IT BECOMES ABSORBED INTO THE AREA OF BROAD LOW PRES LATER ON SAT NIGHT AS IT ADVANCES FURTHER INTO THE WESTERN CARIBBEAN SEA. THE GRADIENT WILL REMAIN THE TIGHTEST OVER THE NORTHERN AND CENTRAL SECTIONS OF THE AREA W OF ABOUT 70W THROUGH SUN. ANOTHER TROPICAL WAVE HAS ENTERED THE FAR EASTERN CARIBBEAN SEA ALONG 62W MOVING W 15 KT. A TROUGH IS JUST NW OF THE TROPICAL N ATLC...AND WILL MOVE INTO THE FAR SE WATERS OF THE SW N ATLC THIS MORNING. ASCAT DATA FROM 0130 TC ALONG BUOY REPORTS NOTED A SWATH OF NE 20-25 KT WINDS W OF THE TROUGH WITH SEAS TO 9 FT. E OF THE TROUGH...E-SE WINDS OF 15 KT ARE OCCURRING. A TROPICAL WAVE WELL E OF THE AREA IS FORECAST TO MOVE INTO THE TROPICAL N ATLC SUN...AND INTO THE EASTERN CARIBBEAN MON...REACHING THE CENTRAL PORTION TUE. THIS WAVE WILL FOLLOWED AGAIN BY INCREASING E-SE WINDS OF 15-20 KT AS DEPICTED IN THE LATEST MODEL GUIDANCE. BOTH GFS AND EUROPEAN 00 UTC RUNS SIMILAR WITH THIS DEPICTION OF THE WINDS E OF THE THE WAVE...BUT WITH MOST OF THE 20 KT WINDS TO BE CONCENTRATED ALONG THE FAR NORTHERN WATERS AND N OF THE CARIBBEAN ACROSS THE SOUTHERN PERIPHERY OF THE SW N ATLC. THE PARALLEL VERSION OF THE GFS INDICATES THAT BULK OF INCREASED ELY WINDS E OF THE WAVE SHOULD BE ALONG THE NORTHERN BOUNDARY OF THE ISLANDS WHERE GRADIENT WILL BE THE TIGHTEST. WAVEWATCH GUIDANCE DOES NOT BUILD SEAS THAT HIGH ACROSS THESE WATERS BEHIND THIS WAVE. IT KEEPS MAXIMUM SEAS CONFINED TO N OF THE AREA THROUGH THE SW N ATLC WHERE THE GRADIENT WILL BE THE STRONGEST...IN COMBINATION WITH BUILDING COMBINED SEAS UNDER LARGE ELY FETCH. SW N ATLC... A RIDGE EXTENDS FROM 30N65W TO N FLORIDA EARLY THIS MORNING ...WHILE AN UPPER LEVEL LOW OVER THE STRAITS OF FLORIDA MOVES W. SCATTERED TSTMS ARE PRESENT BETWEEN THE CENTRAL BAHAMAS AND CUBA. EXPECT GUSTY WINDS WITH THIS ACTIVITY AS IT SPREADS TO THE FAR SW WATERS AND STRAITS OF FLORIDA TODAY INTO EARLY TONIGHT. ANOTHER UPPER LEVEL LOW (TUTT FEATURE) N OF PUERTO RICO NEAR 22N64W IS HELPING TO ENHHANCE SCATTERED TSTMS OVER THE FAR SE WATERS WHICH MAY PRODUCE STRONG WIND GUSTS. SEVERAL SHIP OBSERVATIONS ALONG WITH ASCAT PASSES FROM LATE LAST NIGHT SHOWED NE WINDS OF 20 KT TO THE S OF 25N E OF 70W...AND ALSO S OF 24N W OF 70W INCLUDING THE WINDWARD PASSAGE...AND THOSE BETWEEN THE BAHAMANIAN ISLANDS. THE RIDGE IS FORECAST TO LIFT N TO NEAR 31N BY LATE SUN...AND TO JUST N OF THE AREA MON THROUGH WED.. THE SURFACE TROUGH MENTIONED IN ABOVE SECTION UNDER CARIBBEAN SEA AND TROPICAL N ATLC IS FORECAST TO ENTER THE SE PORTION OF THE AREA THIS AFTERNOON...AND MOVE ACROSS THE SOUTHERN WATERS THROUGH LATE SUN. EASTERLY WINDS OF 20 KT TO POSSIBLY 25 KT ALONG WITH BUILDING SEAS OF 8-11 FT IN E SWELL AS ADVERTISED IN PREVIOUS FORECASTS ARE EXPECTED TO AFFECT THE THE SOUTHERN WATERS E OF THE BAHAMAS ONCE AGAIN EARLY NEXT WEEK AS MODELS WITH THE EXCEPTION OF THE NOGAPS STRONGLY AGREE THAT THESE CONDITIONS WILL MATERIALIZE. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE