000 AXNT20 KNHC 041024 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE AUG 04 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...SPECIAL FEATURES... GALE FORCE WINDS ARE FORECAST TO CONTINUE THROUGH THIS MORNING UNTIL 1800 UTC FROM 11N TO 13N BETWEEN 74W AND 77W. THESE WINDS ARE ASSOCIATED WITH THE TIGHT PRESSURE GRADIENT BETWEEN THE W ATLANTIC SURFACE RIDGE AND A 1006 MB LOW CENTERED OVER N COLOMBIA. PLEASE SEE THE HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE EASTERN ATLANTIC WITH AN AXIS EXTENDING FROM 18N36W TO 09N37W MOVING W AT AROUND 10 KT OVER THE PAST 24 HOURS. MODEL GUIDANCE INDICATES 700 MB TROUGHING FROM 34W TO 39W. SSMI TPW SHOWS THE WAVE AT THE LEADING EDGE OF A POLEWARD SURGE IN TROPICAL MOISTURE. NO DEEP CONVECTION IS ASSOCIATED WITH THIS WAVE. A TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AXIS EXTENDING FROM 20N48W TO 10N48W...MOVING W AT 10 TO 15 KT OVER THE PAST 24 HOURS. THIS WAVE COINCIDES WITH BROAD 700 MB TROUGHING BETWEEN 45W AND 53W. SSMI TPW IMAGERY SHOWS A DRY ENVIRONMENT SURROUNDING THIS WAVE N OF 13N ALONG WITH SAHARAN DUST INDICATED BY METEOSAT IMAGERY. A MOIST ENVIRONMENT IS INDICATED S OF 13N. NO DEEP CONVECTION IS NOTED WITH THIS WAVE. A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN WITH AN AXIS EXTENDING FROM THE WINDWARD PASSAGE AT 20N78W TO 10N79W MOVING W AT 15 KT OVER THE PAST 24 HOURS. THIS WAVE COINCIDES WITH 700 MB TROUGHING BETWEEN 76W AND 81W. ISOLATED MODERATE CONVECTION IS FROM 18N TO 22N BETWEEN 75W AND 82W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS ACROSS AFRICA TO THE E TROPICAL ATLANTIC NEAR 11N15W TO 11N35W AND RESUMES W OF A TROPICAL WAVE NEAR 11N39W TO 10N46W. THE ITCZ EXTENDS W OF A TROPICAL WAVE NEAR 10N49W TO S AMERICA NEAR 10N62W. CLUSTERS OF MODERATE CONVECTION ARE FROM 05N TO 14N BETWEEN 13W AND 21W...WHICH MAY ALSO BE ASSOCIATED WITH A TROPICAL WAVE ABOUT TO EMERGE OFF THE AFRICAN COAST. ISOLATED MODERATE CONVECTION IS ELSEWHERE WITHIN 200 NM OF THE MONSOON TROUGH AND ITCZ AXIS. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE EXTENDS FROM TX TO THE NW GULF WITH AN AXIS THAT EXTENDS E ACROSS N FL. THE UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THE UPPER RIDGE AXIS AND MODERATE MOISTURE SUPPORTS ISOLATED MODERATE CONVECTION FROM 26N TO 30N BETWEEN 86W AND 93W. AN UPPER TROUGH EXTENDS NE FROM THE NW CARIBBEAN TO CENTRAL CUBA AND SUPPORTS ISOLATED THUNDERSTORMS OVER THE FL STRAITS. AT THE SURFACE...A SURFACE RIDGE OVER THE W ATLC EXTENDS AN AXIS ACROSS S FL AND THE CENTRAL GULF. SE WINDS AROUND 10 KT COVER THE S GULF. S TO SW WINDS AROUND 10 KT COVER THE N GULF. A SURFACE TROUGH OVER THE SOUTHERN US WILL NEAR THE NE GULF COAST TODAY...ENHANCING CHANCES FOR CONVECTION OVER THAT PORTION OF THE GULF BASIN. CARIBBEAN SEA... GALE-FORCE WINDS ARE NEAR THE COAST OF N COLOMBIA. PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE DETAILS. STRONG TRADE WINDS ARE OVER THE REMAINDER OF THE S CENTRAL CARIBBEAN. MODERATE TO FRESH TRADE WINDS ARE ELSEWHERE OVER THE CARIBBEAN. A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN. PLEASE SEE THE TROPICAL WAVES SECTION FOR MORE DETAILS. AN UPPER TROUGH THAT EXTENDS ACROSS THE NW CARIBBEAN IS INTERACTING WITH A MODERATELY MOIST AIRMASS TO SUPPORT ISOLATED MODERATE CONVECTION FROM 15N TO 21N BETWEEN 82W AND 87W. THE REMAINDER OF THE CARIBBEAN IS FREE OF DEEP CONVECTION THIS MORNING. CONVECTION WILL CONTINUE OVER THE NW CARIBBEAN TODAY. ...HISPANIOLA... DRY AIR AT THE MID TO UPPER LEVELS IS SPREADING ACROSS THE ISLAND THIS MORNING AS A TROPICAL WAVE AND UPPER TROUGH W OF THE AREA CONTINUES TO MOVE FARTHER FROM HISPANIOLA. PRECIPITATION TODAY WILL BE FROM WEAK SHOWERS IN THE TRADE WIND FLOW OVER THE EASTERN DOMINICAN REPUBLIC...AND ISOLATED THUNDERSTORMS OVER THE ISLAND DUE TO TERRAIN IN THE AFTERNOON. ATLANTIC OCEAN... A MID TO UPPER LEVEL TROUGH EXTENDS FROM THE NW CARIBBEAN TO THE CENTRAL BAHAMAS. A SURFACE TROUGH IS LOCATED UNDER THE TROUGHING ALOFT AND EXTENDS FROM 26N76W TO 22N78W. SCATTERED MODERATE CONVECTION IS FROM 23N TO 27N BETWEEN 72W AND 78W. ANOTHER SURFACE TROUGH IS OVER THE W ATLC FROM 31N68W TO 28N70W SUPPORTING ISOLATED MODERATE CONVECTION WITHIN 100 NM OF THE TROUGH AXIS. SURFACE RIDGING ANCHORED BY A 1027 MB HIGH CENTERED NEAR 35N53W DOMINATES THE CENTRAL AND EASTERN SUBTROPICAL ATLC. TWO TROPICAL WAVES ARE OVER THE TROPICAL ATLC. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE DETAILS. CONVECTION IS EXPECTED TO CONTINUE THROUGH TODAY FROM THE CENTRAL BAHAMAS NORTHWARD TO 31N W OF 72W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO