000 AXNT20 KNHC 271752 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU AUG 27 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 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM ERIKA AS OF 27/1500 UTC WAS CENTERED NEAR 16.4N 63.3W OR ABOUT 110 NM W OF GUADELOUPE...MOVING W AT 14 KT. ESTIMATED CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WINDS ARE 45 KT WITH GUSTS TO 55 KT. CLUSTERS OF MODERATE TO STRONG CONVECTION ARE FROM 12N TO 20N BETWEEN 58W AND 66W. PLEASE SEE THE LATEST FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT5/WTNT25 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE E ATLANTIC WITH AXIS EXTENDING FROM 17N25W TO 09N25W...MOVING W AT ABOUT 15 KT OVER THE PAST 24 HRS. SSMI TPW INDICATES MODERATE MOISTURE S OF 15N IN THE ENVIRONMENT OF THE WAVE. ISOLATED MODERATE CONVECTION IS FROM 08N TO 11N BETWEEN 21W AND 27W. A TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AXIS EXTENDING FROM 21N43W TO 11N44W...MOVING W AT 15 TO 20 KT DURING THE PAST 24 HOURS. A BROAD AREA OF MODERATE MOISTURE IS ASSOCIATED WITH THIS WAVE AS INDICATED BY TPW SSMI IMAGERY. SAHARAN DUST IS ALSO EVIDENT ALONG THE WAVE. NO DEEP CONVECTION IS NOTED WITH THIS WAVE AT THIS TIME. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS INTO THE TROPICAL ATLANTIC NEAR 16N16W TO 12N24W THEN CONTINUES W OF A TROPICAL WAVE NEAR 11N27W TO A 1012 MB LOW NEAR 10N32W. THE ITCZ BEGINS NEAR THIS LOW AND CONTINUES TO 10N43W. OTHER THAN THE CONVECTION ASSOCIATED WITH THE WAVE NEAR THE CAPE VERDE ISLANDS...ISOLATED MODERATE CONVECTION IS FROM 06N TO 14N BETWEEN 28W AND 41W. ...DISCUSSION... GULF OF MEXICO... A MID TO UPPER LEVEL TROUGH EXTENDS FROM THE EASTERN US SW ACROSS THE GULF OF MEXICO WITH A BASE NEAR 20N. THIS TROUGH SUPPORTS A STATIONARY FRONT THAT EXTENDS FROM N FL NEAR 30N83W TO 25N86W TO 23N94W. A PRE-FRONTAL SURFACE TROUGH EXTENDS ACROSS S FL TO 24N83W. SCATTERED MODERATE CONVECTIO0N IS FROM 25N TO 29N BETWEEN THE FRONT AND THE FL PENINSULA. SCATTERED MODERATE CONVECTION IS ALSO OVER THE SW GULF FROM 18N TO 24N BETWEEN 88W AND 97W AND IS BEING SUPPORTED BY A COMBINATION OF THE STATIONARY FRONT AND A DIURNAL SURFACE TROUGH THAT EXTENDS FROM 22N96W TO 18N94W. DRY AIR AND SUBSIDENCE COVERS THE GULF NW OF THE STATIONARY FRONT. 10 TO 15 KT N TO NE WINDS COVER THE GULF N OF THE FRONT AND OVER THE SW GULF. SW WINDS OF 5 TO 10 KT COVER THE SE GULF. THE MID TO UPPER TROUGH WILL REMAIN IN TACT ACROSS THE BASIN THROUGH FRIDAY WHICH WILL SUPPORT CONVECTION OVER THE SOUTHERN AND EASTERN GULF THROUGH THAT TIME. CARIBBEAN SEA... THE BASE OF THE MID TO UPPER LEVEL TROUGH OVER THE GULF RESIDES ALONG 20N. THIS SUPPORTS ISOLATED THUNDERSTORMS OVER THE NW CARIBBEAN N OF 17N W OF 83W. UPPER LEVEL DIFFLUENCE AND DEEP MOISTURE SUPPORTS ISOLATED MODERATE CONVECTION S OF 12N E OF 78W OVER THE SW CARIBBEAN. TROPICAL STORM ERIKA IS OVER THE EASTERN CARIBBEAN. PLEASE REFER TO THE SPECIAL FEATURES SECTION FOR MORE DETAILS. ASIDE FROM THE WINDS ASSOCIATED WITH ERIKA...GENTLE TO MODERATE TRADE WINDS COVER THE CARIBBEAN BASIN. OVER THE NEXT 24 HOURS CONVECTION WILL CONTINUE OVER THE SW CARIBBEAN. CONVECTION AND WINDS ASSOCIATED WITH ERIKA WILL SPREAD W TO NW OVER THE NE CARIBBEAN. ...HISPANIOLA... GENERALLY FAIR CONDITIONS ARE EXPECTED OVER THE WESTERN PORTIONS OF THE ISLAND TODAY. SHOWERS ARE INCREASING THIS AFTERNOON OVER THE EASTERN PORTION OF THE ISLAND WELL IN ADVANCE OF TROPICAL STORM ERIKA. ERIKA IS FORECAST TO MOVE ACROSS PORTIONS OF HISPANIOLA ON FRIDAY. HEAVY RAINFALL WITH FLASH FLOODING AND MUDSLIDES WILL BECOME POSSIBLE FRIDAY THROUGH FRIDAY NIGHT. ATLANTIC OCEAN... A MID TO UPPER LEVEL TROUGH OVER THE EASTERN US AND GULF OF MEXICO SUPPORTS A PRE-FRONTAL SURFACE TROUGH THAT EXTENDS FROM 21N76W TO THE FL STRAITS NEAR 25N81W. SCATTERED MODERATE CONVECTION AND THUNDERSTORMS ARE FROM 25N TO 31N BETWEEN 72W AND THE FL PENINSULA. ANOTHER SURFACE TROUGH...FORMERLY THE REMNANTS OF DANNY...EXTENDS FROM 23N75W TO 19N74W. ISOLATED MODERATE CONVECTION IS N OF 22N WITHIN 30 NM OF THE TROUGH AXIS. CONVECTION ASSOCIATED WITH TROPICAL STORM ERIKA OVER THE EASTERN CARIBBEAN EXTENDS OVER THE CENTRAL ATLC. PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE DETAILS. SURFACE RIDGING OVER THE CENTRAL AND EASTERN ATLC IS ANCHORED BY A PAIR OF SURFACE HIGHS NEAR 28N61W AND 31N25W. THIS RIDGING SUPPORTS GENERALLY FAIR WEATHER OVER THE SUBTROPICAL N ATLC E OF 67W. TWO TROPICAL WAVES ARE OVER THE TROPICAL ATLC. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE DETAILS. OVER THE NEXT 24 HOURS EXPECT CONVECTION TO CONTINUE OVER THE W ATLC OVER THE BAHAMAS AND NEARBY WATERS DUE TO THE PRESENCE OF THE UPPER TROUGH TO THE WEST OF THE AREA. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO