000 AXNT20 KNHC 290555 TWDAT TROPICAL WEATHER DISCUSSION NATIONAL HURRICANE CENTER MIAMI FL 205 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURE... THE 1014 MB LOW NEAR 25N50W WAS UPGRADED TO TROPICAL DEPRESSION ELEVEN AT 29/0300 UTC. TROPICAL DEPRESSION ELEVEN IS CENTERED NEAR 25.2N 50.2W AT 29/0300 UTC OR ABOUT ABOUT 835 NM E-NE OF THE NORTHERN LEEWARD ISLANDS AND ABOUT 880 NM E-SE OF BERMUDA MOVING N 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. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM OF LINE FROM 25N47W TO 28N52W. ...TROPICAL WAVES... TROPICAL WAVE OVER THE CAPE VERDE ISLANDS EXTENDS FROM 18N25W TO 8N27W 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 180 NM W OF THE WAVE BETWEEN 7N-13N WITH CLUSTERS OF SCATTERED MODERATE CONVECTION WITHIN 120 NM EITHER SIDE OF THE REMAINDER OF THE WAVE. TROPICAL WAVE EXTENDS FROM 18N60W TO THE COAST OF VENEZUELA NEAR 8N60W MOVING W NEAR 15 KT. WEAKENING WAVE REMAINS WITHIN AN AREA OF MODERATE MOISTURE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 60 NM OF THE WAVE. TROPICAL WAVE IN THE E CARIBBEAN EXTENDS FROM 15N68W TO INLAND OVER VENEZUELA TO 8N68W MOVING W NEAR 15 KT. THIS WAVE IS RAPIDLY WEAKENING AND IS EMBEDDED WITH AN AREA OF DRY AIR AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. NO ASSOCIATED SHOWERS/CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 14N17W ALONG 12N23W TO 8N30W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 7N45W TO SOUTH AMERICA NEAR 5N52W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE INLAND AND WITHIN 90 NM ALONG THE COAST OF SW AFRICA BETWEEN LIBERIA AND GUINEA...WITHIN 200 NM S OF THE MONSOON TROUGH/ITCZ BETWEEN 23W- 46W...FROM 7N-9N BETWEEN 30W-37W...AND FROM 6N-11N BETWEEN 45W- 55W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE DOMINATES MOST OF THE GULF ANCHORED ALONG THE COAST NEAR GALVESTON TEXAS. A NARROW UPPER TROUGH EXTENDS FROM THE BROAD UPPER TROUGH OVER THE FAR E GULF AND W ATLC ALONG THE COAST OF MEXICO IN THE BAY OF CAMPECHE. THIS BROAD UPPER TROUGH IS SUPPORTING A FRONTAL BOUNDARY IN THE W ATLC AND N CARIBBEAN WITH A SHEAR LINE EXTENDING THROUGH THE YUCATAN CHANNEL NEAR 22N85W TO 24N92W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 45 NM OF THE SHEAR LINE. A SURFACE RIDGE REMAINS ACROSS THE N GULF ANCHORED BY A 1027 MB HIGH OVER NEW ENGLAND. SOME ISOLATED LOW LEVEL SHOWERS ARE OVER THE NE GULF N OF 24N E OF 89W INCLUDING THE FLORIDA KEYS WHERE A POSSIBLE ISOLATED THUNDERSTORM MAY OCCUR. WATER VAPOR IMAGERY INDICATES DRY STABLE AIR COVERS ALL OF THE GULF KEEPING THE REMAINDER OF THE AREA UNDER MOSTLY CLEAR SKIES TONIGHT. WEAK SURFACE RIDGE WILL DOMINATE THE GULF THROUGH TUE. A BROAD TROUGH WILL LIFT OUT OF THE NW CARIBBEAN INTO THE SE 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 THAT EXTENDS FROM THE W ATLC ACROSS CUBA NEAR HOLGUIN OVER THE ISLE OF YOUTH TO 22N85W WHERE IT BECOMES A SHEAR LINE THROUGH THE YUCATAN CHANNEL AND INTO THE GULF OF MEXICO. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 60 NM OF THE FRONT WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 45 NM OF THE SHEAR LINE. AN UPPER RIDGE IS ANCHORED OVER SOUTH AMERICA COVERING THE REMAINDER OF THE CARIBBEAN S OF HISPANIOLA W OF 66W AND IS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS FROM 16N-20N BETWEEN 70W-78W. A WEAK SURFACE TROUGH IS BENEATH THIS UPPER RIDGE EXTENDING FROM 17N78W ALONG 13N79W TO THE COAST OF PANAMA NEAR 9N79W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE S OF 17N BETWEEN 70W-83W. THE MONSOON TROUGH EXTENDS FROM COLOMBIA OVER PANAMA CLIPPING THE FAR SW CARIBBEAN. AN UPPER LOW IS CENTERED OVER THE LESSER ANTILLES NEAR 14N61W COVERING THE E CARIBBEAN. MODERATE TO FRESH E TO SE TRADE WINDS ARE ACROSS S CENTRAL CARIBBEAN THROUGH SUN WHILE GENTLE TO MODERATE WINDS PREVAIL ELSEWHERE THROUGH THU. LOW PRESSURE ACROSS W ATLC WILL LIFT N SUN AND ALLOW SURFACE RIDGE TO STRENGTHEN ACROSS NE CARIBBEAN THROUGH WED. THE SURFACE TROUGH WILL DRIFT NW TOWARD THE NW CARIBBEAN THROUGH WED. HISPANIOLA... CURRENTLY SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 16N- 20N BETWEEN 70W-78W INCLUDING THE GULF OF GONAVE. SOUTHERLY FLOW ALOFT THAT 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 TONIGHT IS NEWLY DEVELOPED 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 29N68W WITH AN OCCLUDED FRONT EXTENDING TO A TRIPLE POINT NEAR 31N66W AND THE COLD FRONT EXTENDING ALONG 26N68W THROUGH THE TURKS AND CAICOS TO ACROSS CUBA NEAR HOLGUIN INTO THE NW CARIBBEAN. SCATTERED SHOWERS/THUNDERSTORMS ARE WITHIN 30/45 NM OF LINE FROM 26N67W TO 31N64W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 23N TO OVER THE GREATER ANTILLES BETWEEN 67W-78W. CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS DOT THE REMAINDER OF THE W ATLC W OF THE FRONT. A BAND OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE N OF THE VIRGIN ISLANDS FROM 18N62W TO 23N61W. THE REMAINDER OF THE ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1022 MB HIGH NEAR 26N39W WITH A WEAKNESS IN THE IMMEDIATE VICINITY OF THE TROPICAL DEPRESSION ELEVEN. THE LOW 1008 MB WILL LIFT N AND EXIT THE REGION SUN WITH THE FRONT LINGERING ACROSS THE BAHAMAS THROUGH MON. A WEAK SURFACE RIDGE WILL DOMINATE THE W ATLC TUE THROUGH THU. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW