000 AXNT20 KNHC 301046 TWDAT TROPICAL WEATHER DISCUSSION NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON SEP 30 2013 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION ELEVEN IS CENTERED NEAR 26.9N 46.7W AT 30/0900 UTC OR ABOUT 1000 NM ESE OF BERMUDA AND ABOUT 1195 NM WSW OF THE AZORES MOVING E AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1010 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 45 KT. SCATTERED MODERATE CONVECTION IS FROM 26N-31N BETWEEN 43W-47W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 06N17W TO 14N17W MOVING W AT 15 KT. THE WAVE COINCIDES WITH A MAXIMUM IN TOTAL PRECIPITABLE WATER IMAGERY THAT HAS EMERGED OFF THE COAST OF AFRICA IN THE VICINITY OF 09N18W. THIS ALONG WITH AN INTERESTING BROAD CYCLONIC CLOUD PRESENTATION EAST OF THE WAVE AXIS IS GENERATING WIDELY SCATTERED MODERATE CONVECTION FROM 07N-12N BETWEEN 18W-26W. TROPICAL WAVE EXTENDS FROM 10N34W TO 21N32W MOVING W AT 15 KT. THE WAVE IS EMBEDDED WITHIN A VERY MOIST ENVIRONMENT AS NOTED TOTAL PRECIPITABLE WATER IMAGERY FROM 07N-20N BETWEEN 27W-36W AND CONTINUES TO COINCIDE WITH SURFACE TO 700 MB TROUGHING AND A RELATIVE VORTICITY MAXIMUM ALONG THE WAVE AXIS NEAR 14N. ISOLATED MODERATE CONVECTION IS FROM 12N-17N BETWEEN 32W-35W. TROPICAL WAVE EXTENDS FROM 15N70W TO 20N67W MOVING W-NW AT 15 KT. THE WAVE IS LOCATED SOUTH OF SUBTROPICAL TROUGHING AS A SURFACE LOW PRESSURE SYSTEM DEVELOPS ACROSS THE SW NORTH ATLC THAT IS FORECAST TO MOVE NORTHWARD OVER THE NEXT 24 TO 36 HOURS. AS A RESULT...ENERGY FROM THE WAVE IS FRACTURING NORTHWARD INTO THIS LOW-LEVEL TROUGHING WHILE ANY REMAINING ENERGY IS EXPECTED TO BECOME DIFFUSE ACROSS THE CENTRAL CARIBBEAN SEA. SCATTERED MODERATE CONVECTION IS FROM 17N-22N BETWEEN 65W-71W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 08N18W TO 09N24W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 09N24W TO 12N33W THEN FROM 09N35W TO 04N51W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 06N-10N BETWEEN 34W-46W. ...DISCUSSION... GULF OF MEXICO... WATER VAPOR IMAGERY INDICATES MUCH OF THE GULF BASIN IS UNDER THE INFLUENCE OF A MIDDLE TO UPPER LEVEL RIDGE ANCHORED OVER THE CENTRAL GULF NEAR 24N90W. OVERALL THIS IS PROVIDING MUCH OF THE BASIN WITH STABLE CONDITIONS THIS MORNING...HOWEVER AN UPPER LEVEL TROUGH AXIS IS NOTED EXTENDING FROM OVER THE OHIO RIVER VALLEY SW TO OVER ARKANSAS AND NORTH TEXAS THAT CONTINUES TO MOVE SOUTHEASTWARD AND EVENTUALLY WILL INTERACT WITH A STATIONARY FRONT ANALYZED FROM THE TEXAS GULF COAST NEAR 29N96W TO NEAR BROWNSVILLE AND INLAND OVER NE MEXICO. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING N OF 23N W OF 93W WITH ONLY ISOLATED LOW-TOPPED SHOWERS OCCURRING ELSEWHERE AT THIS TIME DUE TO THE OTHERWISE STABLE CONDITIONS ALOFT. WEAK SURFACE RIDGING IS EXPECTED TO REMAIN IN PLACE EXTENDING FROM THE SE CONUS TO THE SW GULF WATERS PROVIDING GENERALLY 10 TO 15 KT E-SE WINDS THROUGH WEDNESDAY. CARIBBEAN SEA... A MIDDLE TO UPPER LEVEL TROUGH AXIS EXTENDS FROM OVER THE SW NORTH ATLC NEAR 22N73W SW TO 20N78W TO A BASE NEAR 17N84W. WEST OF THE TROUGH AXIS...WATER VAPOR IMAGERY INDICATES VERY DRY AIR ALOFT AND OVERALL STABLE CONDITIONS THIS MORNING FOR THE NW CARIBBEAN. BENEATH THE UPPER LEVEL TROUGHING AND AREAS TO THE EAST...MOIST SOUTHWESTERLY FLOW ALOFT CONTINUES TO ADVECT MOISTURE AND CLOUDINESS FROM THE CENTRAL CARIBBEAN N-NE INTO A DEVELOPING LOW PRESSURE SYSTEM NORTH OF BERMUDA IN THE SW NORTH ATLC. THIS MOISTURE...ALONG WITH A SURFACE TROUGH ALONG 79W AND A WEAKENING TROPICAL WAVE ALONG 69W IS PROVIDING FOCUS FOR A BROAD AREA OF WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS FROM 08N-18N BETWEEN 73W-80W...AND FROM 16N-24N BETWEEN 65W-73W. CONVECTION OCCURRING ACROSS THE SW CARIBBEAN IS LIKELY ENHANCED DUE TO A COMPLEX AREA OF SURFACE LOW PRESSURE ANCHORED BY A 1009 MB LOW CENTERED NEAR 14N79W AND A 1010 MB LOW CENTERED TO ITS SOUTHWEST NEAR 12N81W. FINALLY...WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW CENTERED OVER THE SE CARIBBEAN NEAR 10N63W THAT CONTINUES TO DRIFT WEST AND PROVIDE TRINIDAD AND TOBAGO...ALONG WITH THE SOUTHERN WINDWARD ISLANDS WITH INCREASED MOISTURE AND CLOUDINESS. ISOLATED SHOWER ACTIVITY IS EXPECTED TO PERSIST MONDAY GENERALLY SOUTH OF 14N E OF 63W. HISPANIOLA... CURRENTLY MOIST SOUTHWESTERLY FLOW ALOFT EAST OF AN UPPER LEVEL TROUGH AXIS EXTENDING FROM OVER THE SE BAHAMAS SOUTHWEST TO OVER 17N84W IS PROVIDING THE ISLAND WITH PLENTY OF MOISTURE AND CLOUDINESS OVERHEAD THIS MORNING. WITH AN OVERALL UPPER LEVEL DIFFLUENT ENVIRONMENT IN PLACE...SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING AND EXPECTED TO PERSIST THROUGH THE DAY ON MONDAY. THE APPROACH OF A TROPICAL WAVE ALONG 69W IS EXPECTED TO INVIGORATE AFTERNOON AND EVENING CONVECTION. AS THIS AREA OF CLOUDINESS AND PRECIPITATION TRAINS FROM THE S-SW OVER HISPANIOLA AND INTO THE SW NORTH ATLC...ANY PROLONGED HEAVY PRECIPITATION OVER A PARTICULAR AREA WILL RESULT IN LOCALIZED FLOODING AND A HIGHER POTENTIAL FOR MUD SLIDES. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL LOW IS CENTERED OFF THE COAST OF THE CAROLINAS NEAR 34N71W THAT EXTENDS A TROUGH AXIS SOUTHWARD ALONG 70W TO 24N THEN SW TO A BASE OVER THE NW CARIBBEAN SEA. THE TROUGHING SUPPORTS A 1008 MB LOW CENTERED NORTH OF BERMUDA NEAR 36N67W WITH A DISSIPATING STATIONARY FRONT EXTENDING TO 31N67W THE CONTINUING SW AS A SURFACE TROUGH TO 26N71W. WITH LARGE- SCALE MOISTURE TRANSPORT ONGOING AND LOW-LEVEL MOISTURE CONVERGENCE IN THE VICINITY OF THE BOUNDARY...SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITHIN 210 NM EITHER SIDE OF A LINE FROM 32N63W TO 20N70W. THE REMAINDER OF THE SW NORTH ATLC WEST OF THE SURFACE TROUGH REMAINS UNDER MOSTLY FAIR SKIES AND ONLY A FEW ISOLATED SHOWERS. FARTHER EAST...ASIDE FROM TROPICAL DEPRESSION ELEVEN...THE CENTRAL ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1019 MB HIGH CENTERED NEAR 26N54W AND ANOTHER SURFACE RIDGE ACROSS THE EASTERN ATLC ANCHORED BY A 1018 MB HIGH CENTERED NEAR 24N27W. A COLD FRONT CONTINUES TO PASS MAINLY TO THE NORTH OF 28N BETWEEN 26W-44W...WITH A FEW ISOLATED SHOWERS AND TSTMS OCCURRING WITHIN 90 NM EITHER SIDE OF THE FRONT...AND FROM 29N-32N BETWEEN 42W-48W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN