000 AGXX40 KNHC 030633 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 233 AM EDT TUE SEP 3 2013 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS. ...GULF OF MEXICO... MODEL PREFERENCE: LATEST GFS BLENDED INTO PREVIOUS PACKAGE AND NWPS USED FOR WAVE PARAMETERS. MEDIUM CONFIDENCE SW PORTION... HIGH CONFIDENCE ELSEWHERE. AN ATLC RIDGE EXTENDS W ACROSS S FL TURNING NW TO THE TX COASTAL BEND. THE RIDGE WILL LIFT N ACROSS THE EASTERN GULF WITH A HIGH CENTER DEVELOPING NEAR CEDAR KEY FL LATE WED...THEN THE HIGH CENTER WILL SHIFT SLOWLY NW TO JUST S OF THE WESTERN FL PANHANDLE ON THU WHERE IT WILL MEANDER THROUGH SAT. MODEL GUIDANCE HAS REVERTED BACK TO THE SCENARIO OF A WEAK TROUGH DIPPING INTO THE N-CENTRAL GULF WATERS THIS AFTERNOON AHEAD OF A WEAK COLD FRONT THAT WILL REACH AS FAR S AS THE NORTHERN COASTAL PLAINS BEFORE LOSING MOMENTUM AND STALLING ON WED NIGHT. THIS WEAK TROUGH WILL PERSIST N OF THE SURFACE RIDGE ACROSS THE N- CENTRAL AND NW WATERS FINALLY WASHING OUT COMPLETELY LATE THU. THE RESULT OF THESE WEAK FEATURES IS ONLY LIGHT/VARIABLE WINDS...WITH SEAS 2 FT OR LESS...ACROSS THE N HALF OF THE GULF OF MEXICO THROUGH THE PERIOD. A BROAD TROPICAL WAVE OVER THE CENTRAL BAY OF CAMPECHE WILL CONTINUE MOVING W TODAY. A SMALL UPPER CYCLONE APPEARS TO BE CUTTING OFF OVER THE SW GULF OF MEXICO...AND THE LOWER LEVEL TROPICAL WAVE HAS MOVED W OF THE PARENT UPPER TROUGH. THIS WILL DECREASE THE POTENTIAL FOR PRECIP....COMBINED WITH GUIDANCE CONTINUING TO SUGGEST A NW-SE ORIENTATED LOW LEVEL TROUGH WILL DEVELOP EACH DAY...BUT ONLY DURING DAYLIGHT HOURS...ACROSS THE WESTERN BAY OF CAMPECHE...EXPECT THE WAVE WILL BE VERY DIFFICULT TO LOCATE AFTER TODAY. IN ANY EVENT...SE WINDS AT 10-15 KT/SEAS 2-3 FT ARE EXPECTED TO CONTINUE THROUGH SUNRISE THIS MORNING OVER THE S-CENTRAL GULF WATERS...THEN DEVELOP AGAIN TONIGHT. THE GRADIENT WILL TIGHTEN AGAIN ON WED NIGHT WITH E-SE 10-15 KT...SEAS 2-4 FT...EXPECTED ACROSS THE ENTIRE WATERS S OF 25N E OF 93W. THEREAFTER THE GRADIENT SEEMS TO RELAX EACH DAY SUPPORTING MOSTLY E WINDS AT 10 KT...THEN TIGHTEN AGAIN ON THU...FRI AND SAT NIGHTS SUPPORTING E 10-15 KT WINDS ACROSS THE SOUTHERN WATERS...BUT ONLY TO THE E OF 90W. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED INTO PREVIOUS PACKAGE WITH NWPS USED FOR WAVE PARAMETERS HEIGHTS. MEDIUM CONFIDENCE. AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO IS CONTINUING TO ENHANCE SCT RW/ISOLD TS OVER THE CARIBBEAN W OF 83W. A CUT OFF CYCLONE IS DEVELOPING ALONG THE TROUGH..REFER TO GULF OF MEXICO DISCUSSION...SO EXPECT THESE FAVORABLE CONDITIONS FOR CONVECTION TO PERSIST OVER THE FAR NW CARIBBEAN FOR ABOUT ANOTHER 24 HOURS. A TROPICAL WAVE OVER THE E CARIBBEAN HAS BECOME DIFFICULT TO LOCATE AS IT IS MOVING W IN PHASE WITH AN UPPER CYCLONE N OF THE AREA NEAR 21N60W AND EMBEDDED ALONG THE ATLC TUTT. THE AREA OF ENHANCED CONVECTION HAS REMAINED OVER THE LEEWARDS...AND A WEAK LOW TO MID LEVEL CYCLONE CONTINUES TO SPIN NEAR 14N61W. THUS THE WAVE WAS HELD NEARLY STATIONARY ALONG 61W YESTERDAY. THE WAVE IS EXPECTED TO MOVE W REACHING ALONG 70W ON WED NIGHT. BY THEN... THE LOW PRESSURE WILL HAVE FILLED. THE WAVE WILL FURTHER WEAKEN AS IT MOVES REACHES ALONG 77W ON FRI AND ALONG 81W ON SAT. CURRENTLY NE-E WINDS AT 15-20 KT COVER THE WATERS N OF 15N E OF 70W. A SECOND TROPICAL WAVE HAS GAINED CONSIDERABLE LATITUDE OVER THE PAST 24 HOURS AND SHOULD PASS 55W AROUND SUNRISE THIS MORNING. THE WAVE WILL ENTER THE E CARIBBEAN ON WED. SEEMS AS IF THE SECOND WAVE WILL BE WEAKER WITH THE TRADES EXPECTED TO DIMINISH TO 15 KT ACROSS THE WATERS E OF THIS WAVE ON THU...AND THEN GRADUALLY WEAKEN TO MOSTLY 10-15 KT THROUGH THE REMAINDER OF THE PERIOD....WHILE THE W CARIBBEAN WILL EXPERIENCE NE-E 5-10 KT TRADES. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED INTO PREVIOUS PACKAGE WITH MEDIUM CONFIDENCE ACROSS WATERS N OF 27N AND LOW CONFIDENCE ACROSS WATERS S OF 27N. DID NOT USE NWPS FOR WAVE PARAMETERS. A RIDGE EXTENDS FROM 31N60W TO S FL. SW 15 KT WINDS/SEAS 3-4 FT HAVE DEVELOPED N OF 30N W OF 72W AS EXPECTED AND SHOULD PERSIST THROUGH TONIGHT. GUIDANCE IS SUGGESTING A TROUGH WILL DIP S INTO THE FAR NW WATERS ON THU NIGHT THROUGH FRI EFFECTIVELY WEAKENING THE RIDGE WITH LIGHT/VARIABLE WINDS ACROSS THE WATERS N OF 30N W OF 70W LATE IN THE PERIOD. THE NORTHERN EXTENSION OF A TROPICAL WAVE IS CURRENTLY S OF 21N BETWEEN 60-65W ACCOMPANIED BY A ENE-E WIND SHIFT AT 15 KT WITH SEAS 4-6 FT. A SECOND TROPICAL WAVE IS CURRENTLY S OF 20N ALONG 54W ACCOMPANIED BY E WINDS AT 15-20 KT TO THE N OF 16N WITHIN 240 NM EITHER SIDE OF THE WAVE AXIS...MERGING AND REINFORCING THE WIND FIELD ASSOCIATED WITH THE TROPICAL WAVE JUST TO THE W. EXPECT THE E WINDS AT 15-20 KT TO CONTINUE ACROSS THE DISCUSSION WATERS E OF 70W THROUGH MIDDAY WED...WHILE E WINDS AT 10-15 KT CONTINUE ACROSS THE REMAINDER OF THE AREA S OF 27N. IT APPEARS THE EASTERN TROPICAL WAVE WILL SEND A TROUGH OFF TO THE NW LATE IN THE WEEK...ACCOMPANIED BY AN E-SE 10-15 KT WIND SHIFT. THE GRADIENT WILL RELAX W OF 65W BY THE WEEKEND...BUT CONTINUE TO SUPPORT 15-20 KT SE WINDS ACROSS THE WATERS BETWEEN 65W-55W. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER NELSON. NATIONAL HURRICANE CENTER.