000 AGXX40 KNHC 131847 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 245 PM EDT SAT AUG 13 2011 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... A WEAK 1016 MB HIGH IS CENTERED NEAR 27.5N87W WITH A RIDGE NW TO NE TEXAS. THIS FEATURE CONTINUES TO BE THE DOMINANT FEATURE IN THE GULF AS HAS BEEN NOTED DURING THE PAST SEVERAL DAYS. LATEST BUOY OBSERVATIONS FROM THROUGHOUT THE GULF INDICATE A LIGHT TO GENTLE BREEZE ACROSS MUCH OF THE GULF WITH SEAS GENERALLY IN THE 1 TO 3 FT. THE EXCEPTIONS ARE FOUND IN THE NW GULF WHERE A MODERATE SE BREEZE IS IN PLACE AND EXPECTED TO PERSIST THROUGH TONIGHT BEFORE DIMINISHING SUN AS WELL AS ALONG THE NORTHERN AND WESTERN YUCATAN PENINSULA EACH EVENING/NIGHT WHERE DIURNALLY DRIVEN LOCAL EFFECTS WILL BRIEFLY INCREASE WINDS TO A FRESH BREEZE. A WEAK TROPICAL WAVE...CURRENTLY IN THE FAR WESTERN CARIBBEAN SEA ALONG 87W...IS EXPECTED TO ENTER INTO THE THE SW GULF ZONE DURING SUN AFTERNOON AND EVENING...AND BE LOCATED IN THE FAR WESTERN PORTION OF THE SW GULF NEAR THE COAST OF MEXICO BY LATE MON AFTERNOON AND EARLY EVENING. A SURGE OF DEEP ATMOSPHERIC MOISTURE IN ASSOCIATION WITH THE WAVE WILL SPREAD WESTWARD THROUGH THE FAR SOUTHERN PORTIONS OF THE GULF THROUGH AT LEAST TUE...ALLOWING FOR PRECIPITATION TO INCREASE ACROSS THOSE WATERS WITH THE ONLY EFFECTS SEEN IN POSSIBLE GUSTY WINDS GENERATED BY INDUCED SHOWERS AND TSTMS THAT PASS OVER THOSE WATERS. A WEAK FRONTAL TROUGH IS STILL ON TAP TO PUSH INTO THE SE U.S. THROUGH TONIGHT....THEN SETTLE SOUTHWARD INTO THE NE GULF SUN THROUGH TUE. IT SHOULD THEN DISSIPATE IN PLACE WED AS HIGH PRES SHIFTS INTO THE NW GULF THROUGH THU. CARIBBEAN SEA... THE TROPICAL WAVE MENTIONED ABOVE IS PRESENTLY APPROACHING THE COASTS OF THE YUCATAN PENINSULA...BELIZE WITH ITS SOUTHERN TIER PORTION PASSING THROUGH NW HONDURAS. CLUSTERS OF SHOWERS AND TSTMS ARE NOTED OVER THE FAR NW PORTION OF THE SEA WITHIN 240 NM E OF THE WAVE. THE MAIN ISSUE WITH THIS WAVE WILL BE SEEN IN THE SPREADING OF ITS RELATED WESTWARD TO EVENTUALLY INTO THE GULF OF MEXICO SECTIONS STATED ABOVE. BUOYS OBSERVATIONS A ALONG WITH A FEW SHIP OBSERVATIONS ACROSS THE AREA REVEAL AN AREAS OF NE-E 20-25 KT WINDS CONFINED FROM 11N TO 16N BETWEEN 72W AND 82W WHERE THE PRES GRADIENT IS THE TIGHTEST. ELSEWHERE E WINDS ARE IN THE RATHER LIGHT RANGE. THE 20-25 KT WINDS ARE FORECAST TO DIMINISH THROUGH MON AS THE GRADIENT WEAKENS DUE TO ATLC HIGH PRES WEAKENING AS TWO SURFACE LOWS IMPINGE UPON IT FROM THE EAST...POSSIBLY AS TROPICAL CYCLONES. AS MENTIONED IN THE PREVIOUS FORECAST AS A TROPICAL WAVE WELL E OF THE AREA IN THE FAR EASTERN ATLC MOST LIKELY TRACKS INTO THE CARIBBEAN SEA AS AGAIN SUGGEST BY LATEST MODEL RUNS. THIS WILL HAVE INFLUENCE WIND AND SEAS CONDITIONS THROUGHOUT...ESPECIALLY IF THE WAVE BECOMES BETTER DEFINED WITH POSSIBLE LOW PRES EVOLVING ALONG IT. TROPICAL N ATLC W OF 55W... A 1013 MB LOW IS NEAR 19N54W MOVING WNW AT 20 KT. THE LOW IS ON TRACK TO CLIP THE NE CORNER OF THE ZONE THIS EVENING AND INTO EARLY SUN...POSSIBLY AS A TROPICAL CYCLONE...AND WILL CONTINUE ON A NW PATH AWAY FROM THE AREA THROUGH SUN EVENING BEFORE TURNING MORE TO THE N AHEAD OF THE TROUGHING OFF THE U.S. SE COAST. THE TROPICAL WAVE IN THE FAR EASTERN ATLC EXTENDING FROM 16N37W TO 10N35W STILL DOESN'T LOOK ANY BETTER DEFINED THAN LAST NIGHT AND THIS MORNING AS IT STILL LACKS ORGANIZED DEEP CONVECTION. LATEST 12 UTC GFS MODEL RUN STILL LIKES TO TAKE IT STRAIGHT W...AND DEVELOPS A LOW ON IT ON IT MON AFTERNOON OR EVENING AS IT APPROACHES THE ZONE...AND TAKES IT THROUGH THE ZONE DURING TUE. THE OTHER GLOBAL ARE MORE SUBTLE WITH THIS FEATURE. THE NOGAPS STILL LIKES TO DEVELOP A LOW ON IT AS WELL. THE 12 UTC GFS IS AGAIN QUITE FAST WITH THE TIMING IN TAKING THE WAVE AND/OR LOW WESTWARD THAN THE UKMET AND IS GENERALLY IN THE FASTER EDGE OF THE GUIDANCE THAT DOES NOT CLOSE OFF THE LOW LEVEL CIRCULATION. WILL LEAN WITH A SLOWER SPEED...CLOSE TO THE ECMWF FOR THIS FORECAST AND AWAIT FUTURE MODEL RUNS FOR COMPARISONS...AND TO DETERMINE WHETHER A CONSENSUS IS BEING INDICATED BY THEM. AS MENTIONED BEFORE...REGARDLESS OF THE DEVELOPMENT OF A CLOSED CIRCULATION...THE WIND FIELD ON THE NORTHERN EDGE OF THE SYSTEM SHOULD EXPAND AS IT MOVES INTO THE ZONE DUE TO THE INCREASED PRES GRADIENT BETWEEN THIS SYSTEM AND THE SW MIGRATING SUBTROPICAL HIGH IN THE CENTRAL ATLC. SOUTHWEST N ATLC... A WEAK 1019 MB HIGH CENTER IS ANALYZED NEAR 27N68W WHILE IN THE UPPER LEVELS A DEEP LAYER TROUGH IS JUST OFF THE SE U.S. COAST. THIS TROUGH IS SUPPORTING A STATIONARY FRONT ALONG THE FAR NW PORTION WHERE SCATTERED SHOWERS AND TSTMS ARE SEEN N OF 29N BETWEEN 74W AND 78W. THE HIGH WILL SHIFT NE WHILE WEAKENING FURTHER THROUGH SUN NIGHT. WITH THIS SCENARIO...EXPECT LIGHT TO MODERATE WINDS AND FAIRLY TRANQUIL SEAS THROUGH THE WEEKEND WITH THE POSSIBLE EXCEPTION OF SE WATERS WHERE A WESTWARD MOVING INVERTED TROUGH MAY GENERATE SOME FRESH WINDS. AN AREA OF LOW PRES...WITH THE POTENTIAL TO BECOME A TROPICAL CYCLONE...IS E OF THE AREA NEAR 27N60W. IT IS EXPECTED TO PASS JUST TO THE NE OF THE AREA MON NIGHT AND LIFT N OF 31N INTO TUE MORNING AHEAD OF A A WEAK COLD FRONT THAT ENTERS HE NW WATERS TUE AND DISSIPATES WED. A RIDGE WILL THEN BUILDS ALONG 29N WED AND THU BEHIND THIS LOW PRES SYSTEM. WARNINGS... GULF OF MEXICO... .NONE. CARIBBEAN AND TROPICAL N ATLC... .NONE. SW N ATLC... .NONE. 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