000 AGXX40 KNHC 020634 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 234 AM EDT MON SEP 2 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 CENTRAL FL TO THE CENTRAL GULF WATERS...THEN TURNS NW TO THE NE TX COAST. A HIGH PRES CENTER WILL DEVELOP OVER THE E-CENTRAL GULF WATERS TODAY ALONG THIS NEARLY STATIONARY RIDGE AXIS...AND MEANDER ALONG THE AXIS OVER THE NE WATERS THROUGH THE REMAINDER OF THE PERIOD. THE RESULT BEING LIGHT/VARIABLE WINDS WITH SEAS 2 FT OR LESS ACROSS THE N HALF OF THE GULF OF MEXICO THROUGH THE PERIOD. THE NORTHERN EXTENSION OF A TROPICAL WAVE WILL MOVE W INTO THE EASTERN BAY OF CAMPECHE THIS MORNING...AND CONTINUE W REACHING THE MEXICAN COAST LATE WED NIGHT OR EARLY THU. SE WINDS AT 10-15 KT/SEAS 2-3 FT ARE ALREADY OVER THE GULF WATERS S OF 25N W OF 85W. EXPECT THESE WINDS TO BACK SLIGHTLY TO ENE...AND DIMINISH TO 10 KT W OF THE WAVE AXIS AS THE WAVE APPROACHES...THEN VEER BACK TO SE AND INCREASES AGAIN TO 10-15 KT/SEAS 2-4 FT E OF THE WAVE AXIS. SLIGHTLY MORE COMPLICATED WINDS WILL OCCUR OVER THE W BAY OF CAMPECHE WHERE GUIDANCE CONTINUES TO SUGGEST AN INVERTED TROUGH WILL DEVELOP EACH AFTERNOON...WITH N-NE 5 KT WINDS OCCURRING W OF THE NE-SW ORIENTATED TROUGH AXIS. AN UPPER TROUGH EXTENDS S ACROSS THE GULF TO A BASE OVER THE BAY OF CAMPECHE. THE ASSOCIATED UPPER DIFFLUENCE HAS BEEN ENHANCING CONVECTION E OF THE WAVE AXIS...CURRENTLY OVER THE YUCATAN CHANNEL. THIS UPPER TROUGH IS EXPECTED TO CONTINUE TO SHIFT W...THUS EXPECT SCT RW/ISOLD TS TO CONTINUE TO BE ENHANCED E OF THE WAVE AXIS AS IT PASSES THROUGH THE AREA. ...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. THE TROPICAL WAVE CURRENTLY OVER THE YUCATAN CHANNEL CONTINUES TO INTERACT WITH AN UPPER TROUGH RESULTING IN SCT RW/ISOLD TS OVER THE NW CARIBBEAN...GENERALLY N OF 16N BETWEEN 81-86W. THE UPPER TROUGH IS EXPECTED TO CONTINUE TO SHIFT W...SO EXPECT THE ASSOCIATED AREA OF PRECIP TO SHIFT SLOWLY W ACROSS THE FAR NW CARIBBEAN TODAY THROUGH TUE...WITH THESE CONDITIONS SHIFTING COMPLETELY W OF THE AREA ON WED. A SECOND TROPICAL WAVE CURRENTLY ORIENTATED FROM 11N61W TO 21N57W HAS A 1008 MB LOW PRESSURE CENTER ANALYZED ALONG THE WAVE AXIS AT 14N60W. ALTHOUGH NHC MENTIONS THAT THIS LOW HAS THE POTENTIAL TO DEVELOP INTO A TROPICAL CYCLONE AS IT CONTINUES W THROUGH THE CARIBBEAN THIS WEEK...CURRENTLY ONLY 15-20 KT WINDS ARE OBSERVED N OF 15N WITHIN 360 NM W AND WITHIN 240 NM E OF THE WAVE AXIS. GUIDANCE CONSENSUS WEAKENS THE GRADIENT ALONG THE WAVE AS IT CONTINUES WESTWARD THROUGH WED. THEN GRADIENT IS EXPECTED TO INCREASE SUPPORTING 15-20 KT E OF THE WAVE ACROSS THE CENTRAL CARIBBEAN ON WED NIGHT...AND CONTINUE THROUGH FRI. CONVECTION IS CURRENTLY ENHANCED ACROSS THE AREA E OF 70W AND WITH UPPER FEATURES EXPECTED TO BECOME LESS FAVORABLE BY TUE... WILL MENTION LESS PRECIP BY MID WEEK. A THIRD TROPICAL WAVE IS CURRENTLY S OF 18N ALONG 48W IS FORECAST TO GAIN SOME LATITUDE AND REACH ALONG 55W TONIGHT AND MOVE INTO TO E CARIBBEAN BY MID WEEK. THE WAVE IS ACCOMPANIED BY SCT RW/ISOLD TS. WILL CONTINUE THAT PRECIP TREND FOR THE FIRST FEW DAYS. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED INTO PREVIOUS PACKAGE WITH MEDIUM CONFIDENCE. NWPS USED FOR WAVE PARAMETERS A STATIONARY FRONT EXTENDS FROM 31N60W TO 26N65W AND EFFECTIVELY SEPARATES THE ATLC RIDGE INTO 2 SEGMENTS. A WEAK 1017 MB HIGH IS CENTERED NEAR 29N68W WITH A RIDGE EXTENDING WSW TO CENTRAL FL. S-SW 15 KT WINDS/SEAS 5 FT IS NOTED N OF 30N WITHIN 180 NM E OF THE STALLED FRONT...BUT SHOULD DIMINISH BELOW 15 KT BY THIS AFTERNOON OVER THE WATERS S OF 31N. REMNANTS OF THE FRONT SHOULD WASH OUT COMPLETELY BY MIDDAY TUE AS THE RIDGE BECOMES RE-ESTABLISHED FROM 31N65W TO CENTRAL FL WITH LITTLE CHANGE EXPECTED THROUGH EARLY THU. SOME GUIDANCE IS SUGGESTING A TROUGH WILL DIP S INTO THE FAR NW WATERS LATE THU...BUT LITTLE CONFIDENCE IN THIS SCENARIO ATTM. THE NORTHERN EXTENSION OF A TROPICAL WAVE IS CURRENTLY S OF 21N BETWEEN 58W-63W. EXPECT A SLIGHT NE-E WIND SHIFT AT 15 KT WITH SEAS 4-6 FT TO SPREAD W ACROSS THE ATLC WATERS N OF THE VIRGIN ISLANDS TODAY. THE GRADIENT SEEMS TO TIGHTEN A LITTLE ON TUE SUPPORTING E WINDS AT 15-20 KT EITHER SIDE OF THE WAVE AS IT PASSES THROUGH THE ATLC APPROACH TO THE MONA PASSAGE TUE...AND PASSES THROUGH THE ATLC APPROACH TO THE WINDWARD PASSAGE ON WED AND WED NIGHT. THE GRADIENT SHOULD WEAKEN THEREAFTER WITH ONLY 10-15 KT ALONG THE WAVE AS IT PASSES W THROUGH THE WATERS BETWEEN CUBA AND THE BAHAMAS ON AND FRI. GUIDANCE IS BEGINNING TO FAVOR AN INVERTED TROUGH...OR THE NORTHERN EXTENSION OF THE WAVE CURRENTLY NEAR 60W...TO DEVELOP S OF 26N BETWEEN 65-70W ON FRI...ACCOMPANIED BY A 10-15 KT E-SE WIND SHIFT. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... GMZ011...NONE. GMZ013...NONE. GMZ015...NONE. GMZ017...NONE. GMZ019...NONE. GMZ021...NONE. GMZ023...NONE. GMZ025...NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... AMZ011...NONE. AMZ013...NONE. AMZ015...NONE. AMZ017...NONE. AMZ019...NONE. AMZ021...NONE. AMZ023...NONE. AMZ025...NONE. AMZ027...NONE. AMZ029...NONE. AMZ031...NONE. AMZ033...NONE. AMZ035...NONE. AMZ037...NONE. AMZ039...NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... AMZ111...NONE. AMZ113...NONE. AMZ115...NONE. AMZ117...NONE. AMZ119...NONE. AMZ121...NONE. AMZ123...NONE. AMZ125...NONE. AMZ127...NONE. *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANES.GOV/MARINE $$ .FORECASTER NELSON. NATIONAL HURRICANE CENTER.