000 AXNT20 KNHC 261711 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SAT SEP 26 2015 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1645 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION IDA IS CENTERED NEAR 24.0N 46.5W AT 26/1500 UTC OR ABOUT 990 NM E-NE OF THE NORTHERN LEEWARD ISLANDS...MOVING NW AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SCATTERED MODERATE CONVECTION IS FROM 23N TO 26N BETWEEN 41W AND 46W. PLEASE SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IS OVER THE EASTERN ATLC WITH AN AXIS THAT EXTENDS FROM 13N32W TO 05N33W...MOVING W NEAR 5 KT OVER THE PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS ALONG THE LEADING EDGE OF A SURGE OF MODERATE/DEEP MOISTURE. ISOLATED MODERATE CONVECTION IS FROM 05N TO 14N BETWEEN 30W AND 40W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION ARE FROM 13N TO 16N BETWEEN 25W AND 30W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 12N16W TO 11N22W TO E OF THE TROPICAL WAVE NEAR 09N31W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION ARE WITHIN 100 NM OF THE MONSOON TROUGH AXIS E OF 20W. ...DISCUSSION... GULF OF MEXICO... AN UPPER TROUGH IS OVER TX AND THE S CENTRAL US...SUPPORTING MOIST SW FLOW ALOFT ACROSS MUCH OF THE GULF OF MEXICO. THE COMBINATION OF DEEP MOISTURE AND WEAK UPPER LEVEL DIFFLUENCE SUPPORTS SCATTERED THUNDERSTORMS ACROSS MUCH OF THE GULF WATERS FROM 24N TO 29N BETWEEN 82W AND 97W. THERMODYNAMIC INFLUENCES ALONG THE MEXICO COAST SUPPORTS ISOLATED THUNDERSTORMS FROM 21N TO 24N W OF 96W. A BROAD TROUGH OF LOW PRESSURE EXTENDS FROM NEAR 23N87W TO THE YUCATAN PENINSULA TO THE GULF OF HONDURAS. ISOLATED MODERATE CONVECTION IS WITHIN 150 NM TO THE E OF THE TROUGH AXIS. MODERATE N TO NE WINDS COVER THE NORTHERN GULF. VARIABLE GENTLE TO MODERATE WINDS COVER THE SOUTHERN GULF...EXCEPT HIGHER NEAR CONVECTION. OVER THE NEXT 48 HOURS THE TROUGH OVER THE S CENTRAL GULF WILL DRIFT NORTHWARD AND DEVELOP INTO A SURFACE LOW WITH CONVECTION. THE TROUGH OVER TX WILL CUT OFF INTO AN UPPER LOW...SUPPORTING CONVECTION OVER THE NW AND N CENTRAL GULF. CARIBBEAN SEA... UPPER RIDGING PROVIDES A DIFFLUENT ENVIRONMENT ALOFT ACROSS THE WESTERN CARIBBEAN...WHILE UPPER LEVEL TROUGHING DOMINATES THE EASTERN CARIBBEAN WITH A TROUGH AXIS OVER THE LESSER ANTILLES. A SURFACE TROUGH EXTENDS FROM THE S CENTRAL GULF AND THE NE YUCATAN PENINSULA NEAR 20N88W TO THE GULF OF HONDURAS NEAR 16N88W. THE UPPER DIFFLUENCE ASSOCIATED WITH THE UPPER RIDGE IS INTERACTING WITH THE TROUGH TO SUPPORT SCATTERED MODERATE CONVECTION FROM 16N TO 22N BETWEEN 84W AND 89W. THE UPPER DIFFLUENCE ALSO SUPPORTS A CLUSTER OF MODERATE CONVECTION OVER THE SW CARIBBEAN FROM 09N TO 13N BETWEEN 79W AND 84W. GENTLE TO MODERATE TRADE WINDS ARE N OF A LINE FROM 20N84W TO 12N62W. MAINLY MODERATE TO FRESH TRADE WINDS ARE S OF THIS LINE. OVER THE NEXT 24 HOURS CONVECTION WILL CONTINUE OVER THE NW CARIBBEAN WITH THE SURFACE TROUGH IN THE AREA. ...HISPANIOLA... SHALLOW MOISTURE COMBINED WITH DAYTIME HEATING WILL SUPPORT ISOLATED THUNDERSTORMS ACROSS THE ISLAND TODAY. MOISTURE ASSOCIATED WITH A TROUGH TO THE NORTH OF HISPANIOLA MAY SPREAD ACROSS PORTIONS OF THE ISLAND ON SUNDAY SUPPORTING SCATTERED THUNDERSTORMS MAINLY DURING THE AFTERNOON AND EVENING. ATLANTIC OCEAN... A SURFACE TROUGH IS OVER THE SW N ATLC EXTENDING FROM 29N69W TO 22N70W AND IS INTERACTING WITH AN UPPER LOW CENTERED NEAR 28N70W. SCATTERED MODERATE CONVECTION IS FROM 21N TO 29N BETWEEN 62W AND 70W. TROPICAL DEPRESSION IDA IS OVER THE CENTRAL ATLC. PLEASE REFER TO THE SPECIAL FEATURES SECTION FOR MORE DETAILS. OTHER CONVECTION OVER THE E TROPICAL ATLC W OF THE CAPE VERDE ISLANDS IS PRIMARILY ASSOCIATED WITH A TROPICAL WAVE. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE DETAILS. OVER THE NEXT 24 HOURS CONVECTION WILL CONTINUE NEAR THE SURFACE TROUGH OVER THE SW N ATLC AND NEAR TROPICAL DEPRESSION IDA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO