000 AXNT20 KNHC 071743 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN SEP 07 2014 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 WAVE EXTENDS FROM A 1010 MB LOW CENTERED NEAR 09N16W TO A 1010 MB LOW CENTERED NEAR 17N17W TO 20N17W MOVING W-NW AT 10- 15 KT. SATELLITE IMAGERY INDICATES A STOUT PRESENTATION OF CYCLONIC TURNING STRONGEST IN THE 850 MB TO 700 MB LEVELS WITHIN GLOBAL MODEL GUIDANCE. THE STRONGER CIRCULATION REMAINS THE SOUTHERN LOW WITH RELATIVELY VORTICITY MAXIMIZED NEAR 10N ALONG THE WAVE AXIS. SCATTERED MODERATE CONVECTION IS FROM 05N-09N BETWEEN 18W-22W...WITH ISOLATED MODERATE CONVECTION ELSEWHERE FROM 05N-13N BETWEEN 11W-23W. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 12N34W TO 22N36W MOVING W AT 15-20 KT. A 1013 MB LOW IS CENTERED ALONG THE WAVE AXIS NEAR 15N THAT HAS FRACTURED NORTH OF THE INFLUENCE OF THE MONSOON TROUGH. THE FRACTURE IS DUE IN LARGE PART TO A RELATIVELY HIGH AMPLITUDE 700 MB TROUGH BETWEEN 31W-41W THAT IS PLACED BETWEEN TWO SUBTROPICAL 700 MB ANTICYCLONIC CIRCULATIONS...ONE NEAR 22N22W AND THE OTHER NEAR 21N48W. SCATTERED MODERATE CONVECTION IS FROM 14N-18N BETWEEN 30W-33W. TROPICAL WAVE EXTENDS FROM 11N71W TO 20N64W MOVING W AT 20-25 KT. THE WAVE COINCIDES WITH BROAD 700 MB TROUGHING EXTENDING FROM THE SOUTH-CENTRAL CARIBBEAN SEA AND OVER THE REGION NORTH OF PUERTO RICO AND THE MONA PASSAGE. WIDELY SCATTERED MODERATE CONVECTION IS FROM 15N-20N BETWEEN 64W-70W. TROPICAL WAVE EXTENDS FROM 11N86W TO 22N85W MOVING W AT 15-20 KT. THE WAVE CONTINUES TO MOVE WITHIN A FAIRLY LARGE AREA OF MAXIMUM TOTAL PRECIPITABLE WATER AS NOTED ON RECENT IMAGERY ACROSS THE NW CARIBBEAN SEA AND SOUTHERN PORTIONS OF THE GULF OF MEXICO. ISOLATED MODERATE CONVECTION IS FROM 14N-22N BETWEEN 80W- 89W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 10N18W TO 13N33W TO 08N38W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N38W TO 08N50W. NO SIGNIFICANT DEEP CONVECTION IS OCCURRING OUTSIDE OF CONVECTION ASSOCIATED WITH THE TROPICAL WAVES MENTIONED ABOVE. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL LOW IS CENTERED OVER EAST-CENTRAL MEXICO NEAR 20N99W THAT EXTENDS TROUGHING ALOFT TO THE NE OVER THE MUCH OF THE NORTH-CENTRAL AND WESTERN GULF THIS AFTERNOON. THE BROAD UPPER LEVEL CYCLONIC CIRCULATION IS PROVIDING AN OVERALL UNSTABLE ENVIRONMENT FOR THE ENTIRE BASIN GENERATING AREAS OF ISOLATED SHOWERS AND TSTMS. CONVECTION IS CONCENTRATED IN THE VICINITY OF A SURFACE TROUGH EXTENDING FROM 19N94W TO 22N97W AND WITHIN 60 NM EITHER SIDE OF A LINE FROM 21N95W TO 23N87W. ACROSS THE NORTHERN WATERS...A COLD FRONT REMAINS ANALYZED ACROSS THE SE CONUS...LOUISIANA...AND SOUTHEASTERN TEXAS. LOW-LEVEL MOISTURE CONVERGENCE ACROSS THE NORTHERN GULF WATERS IN TANDEM WITH THE FAVORABLE UPPER LEVEL DYNAMICS IS GENERATING ISOLATED SHOWERS AND TSTMS GENERALLY NORTH OF 27N AND WITHIN 150 NM OFFSHORE OF THE WESTERN FLORIDA PENINSULA COAST. OTHERWISE... WEAK SURFACE RIDGING EXTENDS FROM THE SW NORTH ATLC ACROSS THE SOUTHERN FLORIDA PENINSULA TO A 1016 MB HIGH CENTERED NEAR 26N95W. AMIDST ALL THE ISOLATED CONVECTION OCCURRING...LIGHT ANTICYCLONIC WINDS IN THE RANGE OF 5 TO 15 KT ACCOMPANY THE RIDGING THAT IS FORECAST TO SHIFT SLIGHTLY NORTH DURING THE NEXT 24 TO 36 HOURS. CARIBBEAN SEA... A PAIR OF TROPICAL WAVES ARE IMPACTING WEATHER ACROSS THE CARIBBEAN THIS AFTERNOON WITH THE WESTERN-MOST WAVE IMPACTING THE NW CARIBBEAN AND PORTIONS OF CENTRAL AMERICA. THE WAVE EXTENDS FROM THE WESTERN TIP OF CUBA SOUTHWARD ACROSS CENTRAL HONDURAS AND WESTERN NICARAGUA. WIDELY SCATTERED SHOWERS AND TSTMS ARE OCCURRING IN ASSOCIATION WITH THE WAVE FROM 14N-22N BETWEEN 80W-89W. FARTHER SOUTH...THE MONSOON TROUGH AXIS EXTENDS ALONG 10N WEST OF NORTHERN COLOMBIA AND CONTINUES TO PROVIDE FOCUS FOR SCATTERED SHOWERS AND TSTMS S OF 12N BETWEEN 78W-85W. TO THE EAST...A TROPICAL WAVE EXTENDS FROM NE OF PUERTO RICO TO THE COAST OF NW VENEZUELA WITH SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING FROM 15N-20N BETWEEN 65W-70W...INCLUDING THE US/UK VIRGIN ISLANDS...PUERTO RICO...THE MONA PASSAGE...AND PORTIONS OF EASTERN DOMINICAN REPUBLIC. THE MAJORITY OF THIS CONVECTION...WHILE ASSOCIATED WITH A TROPICAL WAVE...IS ALSO IMPACTED BY AN UPPER LEVEL LOW CENTERED OVER THE SW NORTH ATLC REGION NEAR 23N73W THAT DIPS TROUGHING SOUTHEASTWARD TO A BASE NEAR 15N65W. OTHERWISE...THE WAVES ARE EXPECTED TO CONTINUE MOVING THROUGH GENERALLY MODERATE TO FRESH TRADES DURING THE NEXT FEW DAYS. ...HISPANIOLA... CURRENTLY HISPANIOLA IS INFLUENCED BY UPPER LEVEL WEST- NORTHWESTERLY WINDS ALOFT THAT TRANSITION TO MORE DIFFLUENT FLOW E OF 71W THIS AFTERNOON. WITH AN UPPER LEVEL LOW CENTERED OVER THE SW NORTH ATLC TO THE NORTH OF THE ISLAND NEAR 23N73W... MOISTURE AND CLOUDINESS CONTINUES TO ADVECT ACROSS THE ISLAND. IN ADDITION...A TROPICAL WAVE LIES TO THE SE OF THE ISLAND THAT IS FORECAST TO INTRODUCE MORE MOISTURE...SCATTERED SHOWERS... AND TSTMS THROUGH THE EVENING AND OVERNIGHT HOURS INTO MONDAY. CONVECTIVE ACTIVITY IS CURRENTLY ONGOING ACROSS THE MONA PASSAGE AND FAR EASTERN DOMINICAN REPUBLIC. ATLANTIC OCEAN... UPPER LEVEL DIFFLUENCE ALONG WITH MID-LEVEL ENERGY FOCUSED OVER NORTHERN FLORIDA IS GENERATING WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS N OF 23N W OF 79W THIS AFTERNOON ACROSS THE FAR WESTERN PORTION OF THE SW NORTH ATLC. THIS CONVECTION REMAINS ON THE WESTERN PERIPHERY OF AN UPPER LEVEL LOW CENTERED NEAR 23N73W THAT CONTINUES TO GENERATE SCATTERED SHOWERS AND TSTMS FROM 18N- 28N BETWEEN 65W-75W. OTHERWISE...THE REMAINDER OF THE SW NORTH ATLC IS UNDER THE INFLUENCE OF A WEAK SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NE OF BERMUDA NEAR 35N59W. FARTHER EAST...A COMPLEX MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 30N51W WITH THE ASSOCIATED TROUGH AXIS EXTENDING SW TO A BROAD BASE NEAR 25N60W. THE TROUGHING SUPPORTS A PAIR OF WEAK 1018 MB LOWS CENTERED NEAR 28N50W AND NEAR 29N56W. A SURFACE TROUGH EXTENDS THROUGH THE LATTER LOW FROM 31N50W TO 28N57W TO 29N63W. A BROAD AREA OF ISOLATED SHOWERS AND TSTMS IS OCCURRING FROM 25N- 30N BETWEEN 44W-64W. OTHERWISE...THE REMAINDER OF THE EASTERN ATLC IS UNDER RELATIVELY TRANQUIL CONDITIONS...OUTSIDE OF TROPICAL WAVE INFLUENCES...AS A RIDGE ANCHORED BY A 1021 MB HIGH CENTERED NEAR 28N31W IS IN CONTROL ACROSS THE REGION. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN