000 AXNT20 KNHC 051025 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT WED AUG 05 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... A TIGHT PRESSURE GRADIENT BETWEEN W ATLC HIGH PRESSURE AND LOW PRESSURE OVER N COLOMBIA SUPPORTS GALE FORCE WINDS FROM 11N TO 14N BETWEEN 72W AND 76W. THE GALE-FORCE WINDS ARE FORECAST TO PERSIST UNTIL 1800 UTC TODAY. SEE THE LATEST NWS HIGH SEAS FORECAST UNDER AWIPS/WMO HEADERS MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE E ATLANTIC WITH AN AXIS EXTENDING FROM 19N30W TO 10N28W...MOVING W AT 15 TO 20 KT. THE WAVE COINCIDES WITH AN INVERTED 700 MB TROUGH BETWEEN 27W AND 33W. SSMI TPW IMAGERY INDICATES MODERATE MOISTURE OVER THE WAVE ENVIRONMENT. NO DEEP CONVECTION IS NOTED. A LOW AMPLITUDE TROPICAL WAVE IS OVER THE CENTRAL ATLANTIC WITH AN AXIS EXTENDING FROM 16N40W TO 10N40W...MOVING W AT AROUND 10 KT OVER THE PAST 24 HOURS. THE WAVE COINCIDES WITH A SUBTLE 700 MB TROUGH BETWEEN 38W AND 42W. HIGH MOISTURE IS LOCATED S OF 13N AND DRY AIR IS N OF 13N IN THE WAVE ENVIRONMENT. NO DEEP CONVECTION IS NOTED WITH THIS WAVE. A TROPICAL WAVE IS APPROACHING THE LESSER ANTILLES WITH AN AXIS EXTENDING FROM 19N58W TO 11N59W...MOVING W AT 15 TO 20 KT OVER THE PAST 24 HOURS. THE WAVE COINCIDES WITH BROAD 700 MB TROUGHING BETWEEN 51W AND 65W. ISOLATED MODERATE CONVECTION IS FROM 11N TO 13N BETWEEN 57W AND 60W. A TROPICAL WAVE IS EXITING THE W CARIBBEAN AND MOVING ACROSS ENTERING CENTRAL AMERICA WITH AN AXIS EXTENDING FROM 20N88W TO 09N88W...MOVING W AT 20 TO 25 KT OVER THE PAST 24 HOURS. THE INTERACTION OF THIS WAVE WITH AN UPPER LOW IS SUPPORTING SCATTERED MODERATE CONVECTION FROM 15N TO 21N BETWEEN 82W AND 89W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 13N17W THROUGH A 1010 MB LOW NEAR 11N20W TO 11N27W...THEN RESUMES W OF A TROPICAL WAVE NEAR 11N29W TO 09N39W. THE ITCZ BEGINS W OF A TROPICAL WAVE NEAR 11N41W AND CONTINUES THROUGH A 1012 MB LOW NEAR 12N48W TO 10N57W. A SURFACE TROUGH EXTENDS NORTH OF THIS LOW TO 17N47W. CLUSTERS OF MODERATE CONVECTION ARE WITHIN 175 NM OF THE 1010 MB LOW OVER THE EASTERN ATLC. WIDELY SCATTERED MODERATE CONVECTION IS FROM 05N TO 11N BETWEEN 23W AND 36W...AND FROM 09N TO 13N BETWEEN 41W AND 57W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL TROUGH EXTENDS FROM THE NW CARIBBEAN TO THE SE GULF. THIS IS SUPPORTING SCATTERED THUNDERSTORMS OVER THE GULF FROM 22N TO 26N BETWEEN 81W AND 85W. AN UPPER RIDGE AXIS EXTENDS FROM TX E TO THE FL PANHANDLE. UPPER LEVEL DIFFLUENCE ASSOCIATED WITH THIS RIDGE SUPPORTS ISOLATED MODERATE CONVECTION FROM 29N TO 31N BETWEEN 88W AND 90W. A 1018 MB HIGH CENTERED NEAR 28N83W IS PART OF A BROAD SURFACE RIDGE THAT EXTENDS FROM THE W ATLC TO CENTRAL FL TO THE TX COAST. MODERATE E TO SE WINDS COVER MOST OF THE GULF S OF 28N...WITH MODERATE S TO SW WINDS N OF 28. LIGHTER WINDS ARE NEAR THE RIDGE AXIS OVER THE EAST CENTRAL GULF. CONVECTION IS FORECAST TO CONTINUE OVER THE SE GULF TODAY...AND SPREAD WESTWARD TOWARD THE SW GULF THIS AFTERNOON. CARIBBEAN SEA... AN UPPER LEVEL TROUGH EXTENDS FROM NICARAGUA ACROSS THE NW CARIBBEAN. THIS UPPER TROUGH IS INTERACTING WITH A TROPICAL WAVE...SUPPORTING SCATTERED MODERATE CONVECTION FROM 15N TO 21N BETWEEN 82W AND 89W. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE DETAILS. A TIGHT PRESSURE GRADIENT BETWEEN THE W ATLC SURFACE RIDGE AND LOW PRESSURE OVER N COLOMBIA SUPPORTS GALE FORCE WINDS OVER A PORTION OF THE S CENTRAL CARIBBEAN. PLEASE SEE THE SPECIAL FEATURES SECTION FOR MORE DETAILS. FRESH TO STRONG TRADE WINDS EXTEND ACROSS MUCH OF THE REMAINDER OF THE CENTRAL CARIBBEAN WITH MODERATE TO FRESH TRADE WINDS ELSEWHERE. CONVECTION WILL CONTINUE UNDER THE UPPER TROUGH OVER THE NW CARIBBEAN TODAY. A TROPICAL WAVE WILL BRING SHOWERS TO THE LESSER ANTILLES TODAY AS IT ENTERS THE EASTERN CARIBBEAN FROM THE ATLC. ...HISPANIOLA... ISOLATED SHOWERS IN LOW LEVEL MOISTURE IN TRADE WIND FLOW ARE MOVING ACROSS PORTIONS OF THE DOMINICAN REPUBLIC THIS MORNING. OTHERWISE...FAIR WEATHER EXTENDS ACROSS THE ISLAND. THIS MOISTURE MAY RESULT IN ISOLATED THUNDERSTORMS THIS AFTERNOON. ADDITIONAL SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE BY THURSDAY AS A TROPICAL WAVE PASSES BY THE ISLAND. ATLANTIC OCEAN... A SURFACE TROUGH EXTENDS FROM 28N77W TO 24N80W SUPPORTING ISOLATED MODERATE CONVECTION WITHIN 30 NM OF THE TROUGH AXIS...INCLUDING THE N BAHAMAS. FARTHER EAST...AN UPPER LOW CENTERED NEAR 28N57W SUPPORTS A PAIR OF SURFACE TROUGHS OVER THE CENTRAL ATLC FROM 26N61W TO 21N63W...AND FROM 28N51W TO 21N51W. SCATTERED SHOWERS ARE WITHIN 100 NM OF BOTH OF THE SURFACE TROUGH AXIS. SCATTERED THUNDERSTORMS ARE WITHIN 150 NM OF THE UPPER LOW. SURFACE RIDGING ANCHORED BY A 1026 MB HIGH CENTERED NEAR 35N50W EXTENDS ACROSS THE REMAINDER OF THE SUBTROPICAL ATLC. THREE TROPICAL WAVES ARE OVER THE TROPICAL ATLC. PLEASE REFER TO THE TROPICAL WAVES SECTION FOR MORE DETAILS. TWO LOW PRESSURE SYSTEMS AND A SURFACE TROUGH ARE OVER THE TROPICAL ATLC. PLEASE REFER TO THE ITCZ/MONSOON TROUGH SECTION FOR MORE DETAILS. CONVECTION WILL CONTINUE WITH THE W ATLC SURFACE TROUGH OVER THE BAHAMAS TODAY...AS WELL AS WITH THE UPPER LOW OVER THE CENTRAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO