000 AXNT20 KNHC 291047 TWDAT TROPICAL WEATHER DISCUSSION NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN SEP 29 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 FEATURE... TROPICAL DEPRESSION ELEVEN IS CENTERED NEAR 25.6N 49.7W AT 29/0900 UTC OR ABOUT ABOUT 870 NM E-NE OF THE NORTHERN LEEWARD ISLANDS AND ABOUT 890 NM E-SE OF BERMUDA MOVING NE AT 8 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1010 MB. MAXIMUM SUSTAIN WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. PLEASE SEE LATEST NHC PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC AND THE FULL ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 25N-29N BETWEEN 46W-50W. ...TROPICAL WAVES... TROPICAL WAVE JUST W OF THE CAPE VERDE ISLANDS EXTENDS FROM 18N26W TO 7N29W MOVING W NEAR 15 KT. WAVE REMAINS EMBEDDED WITHIN A SURGE OF DEEP MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE/ ISOLATED CONVECTION ARE WITHIN 150 NM W OF THE WAVE BETWEEN 7N- 15N WITH CLUSTERS OF SCATTERED MODERATE CONVECTION WITHIN 150 NM EITHER SIDE OF THE REMAINDER OF THE WAVE. TROPICAL WAVE EXTENDS FROM 21N62W INTO THE CARIBBEAN TO 13N63W MOVING W-NW NEAR 20 KT. WAVE IS MOVING AROUND THE BROAD SURFACE RIDGE THAT DOMINATES THE CENTRAL AND E ATLC. WAVE REMAINS EMBEDDED WITHIN AN AREA OF MODERATE MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE FROM 14N-20N BETWEEN 60W- 65W. TROPICAL WAVE IN THE E CARIBBEAN IS NO LONGER DISCERNIBLE AND WAS DROPPED FROM THE 29/0600 UTC ANALYSIS. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 12N16W TO 10N24W. THE ITCZ BEGINS W OF THE TROPICAL WAVE NEAR 9N31W AND CONTINUES ALONG 7N36W 7N51W TO SOUTH AMERICA NEAR 6N57W. SCATTERED MODERATE/STRONG CONVECTION IS WITHIN 150 NM ALONG THE COAST OF SW AFRICA S OF 11N E OF 10W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 225 NM S OF THE ITCZ BETWEEN 30W-43W AND WITHIN 150 NM N OF THE ITCZ W OF 47W TO INLAND OVER SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE DOMINATES THE GULF ANCHORED ALONG THE COAST NEAR CORPUS CHRISTI TEXAS. A NARROW UPPER TROUGH EXTENDS FROM THE BROAD UPPER TROUGH OVER W ATLC AND NW CARIBBEAN ACROSS THE YUCATAN TO INLAND OVER S MEXICO. THIS BROAD UPPER TROUGH IS SUPPORTING A FRONTAL BOUNDARY IN THE W ATLC AND NW CARIBBEAN WITH A SHEAR LINE EXTENDING ACROSS NE YUCATAN PENINSULA NEAR 21N87W ALONG 23N91W TO 27N96W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 75 NM S OF THE SHEAR LINE W OF 93W WITH SCATTERED SHOWERS WITHIN 60 NM S OF THE REMAINDER OF THE SHEAR LINE. A WEAK SURFACE RIDGE REMAINS ACROSS THE N GULF ANCHORED BY A 1024 MB HIGH OVER NEW ENGLAND AND 1023 MB HIGH OVER WESTERN NORTH CAROLINA. A WEAK SURFACE TROUGH IS IN THE E GULF EXTENDING FROM 28N85W TO 24N83W. ISOLATED LOW LEVEL SHOWERS ARE FROM 24N- 29N E OF 90W TO THE COAST OF FLORIDA INCLUDING THE FLORIDA KEYS. WATER VAPOR IMAGERY INDICATES DRY STABLE AIR COVERS ALL OF THE GULF KEEPING THE REMAINDER OF THE AREA UNDER MOSTLY CLEAR SKIES THIS MORNING. WEAK SURFACE RIDGE WILL DOMINATE THE N GULF THROUGH TUE. A BROAD TROUGH OR POSSIBLE LOW WILL LIFT OUT OF THE NW CARIBBEAN INTO THE SOUTHEASTERN GULF LATE WED INTO THU. CARIBBEAN SEA... THE UPPER TROUGH OVER THE FAR E GULF OF MEXICO DIPS S OVER THE NW CARIBBEAN N OF LINE FROM THE WINDWARD PASSAGE TO THE TIP OF NICARAGUA/HONDURAS SUPPORTING A COLD FRONT IN THE W ATLC THAT ENTERS THE CARIBBEAN AS A STATIONARY FRONT ACROSS CUBA JUST SE HOLGUIN TO THE ISLE OF YOUTH WHERE IT BECOMES A SHEAR LINE INTO THE GULF OF MEXICO OVER NE YUCATAN PENINSULA. AN UPPER RIDGE AXIS EXTENDS FROM COLOMBIA TO HISPANIOLA AND IS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE CENTRAL CARIBBEAN FROM 11N-20N BETWEEN 70W-78W. A SURFACE TROUGH IS BENEATH THIS UPPER RIDGE EXTENDING FROM 11N75W ALONG 15N76W TO 19N75W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA NEAR 11N74W ALONG 13N79W ACROSS NICARAGUA NEAR 12N84W GENERATING SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS S OF 15N BETWEEN 78W-84W. WEAK SURFACE RIDGE ACROSS THE CENTRAL ATLC WILL MAINTAIN MODERATE TO FRESH E TO SE TRADE WINDS ACROSS S/CENTRAL CARIBBEAN THROUGH THIS EVENING. LOW PRESSURE ACROSS W ATLC WILL LIFT N TODAY AND TONIGHT AND ALLOW A SURFACE RIDGE TO STRENGTHEN ACROSS NE CARIBBEAN AND FRESHEN TRADE WINDS ACROSS E CARIBBEAN THROUGH WED. DEVELOPING SURFACE LOW ACROSS SW CARIBBEAN WILL DRIFT NW TOWARD THE NW CARIBBEAN THROUGH WED. HISPANIOLA... CURRENTLY SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE S OF 20N W OF 70W INCLUDING THE GULF OF GONAVE AND THE WINDWARD PASSAGE. SOUTHERLY FLOW ALOFT WILL CONTINUE THROUGH MON WHEN WINDS WILL SHIFT TO WESTERLY THEN NORTHERLY ON TUE AS AN UPPER RIDGE MOVES ACROSS THE N/CENTRAL CARIBBEAN AND BE W OF THE ISLAND BY WED. THIS WILL INCREASE THE CHANCE OR INTENSIFY AFTERNOON SHOWERS AND THUNDERSTORMS THROUGH MON. TUE THROUGH FRI WILL BE A SLIGHTLY LESS CHANCE OF HEAVY AFTERNOON SHOWERS/THUNDERSTORMS. ATLANTIC OCEAN... THE HIGHLIGHT THIS MORNING IS TROPICAL DEPRESSION ELEVEN IN THE CENTRAL ATLC. SEE SPECIAL FEATURES ABOVE. AN UPPER TROUGH COVERS THE W ATLC W OF 64W ACROSS FLORIDA AND DIPS S OVER THE NW CARIBBEAN SUPPORTING A FRONTAL BOUNDARY THAT EXTENDS FROM A 1008 MB LOW NEAR 30N67W WITH AN OCCLUDED FRONT EXTENDING TO A TRIPLE POINT NEAR 32N63W AND THE COLD FRONT EXTENDING TO 26N68W WHERE IT BECOMES STATIONARY THROUGH THE TURKS AND CAICOS TO ACROSS CUBA JUST SE HOLGUIN INTO THE NW CARIBBEAN. SCATTERED SHOWERS/ THUNDERSTORMS ARE WITHIN 120 NM E OF THE FRONT WITH CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 200 NM W OF THE FRONT. THE REMAINDER OF THE ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1020 MB HIGH NEAR 27N37W WITH A WEAKNESS IN THE IMMEDIATE VICINITY OF THE TROPICAL DEPRESSION ELEVEN. FRONT WILL DRIFT SE AND WEAKEN THROUGH TONIGHT. ELONGATED LOW PRESSURE JUST TO THE NW OF FRONT WILL LIFT N AND EXIT THE REGION TODAY AND TONIGHT. A WEAK RIDGE WILL DOMINATE THE ATLC TUE THROUGH THU. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW