000 AXNT20 KNHC 030547 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU SEP 03 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...SPECIAL FEATURES... TROPICAL STORM FRED IS CENTERED NEAR 20.6N 32.7W AT 03/0300 UTC OR ABOUT 570 NM W-NW OF THE CAPE VERDE ISLANDS MOVING W-NW AT 9 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. THE STRONG WESTERLY VERTICAL WIND SHEAR REMAINS ACROSS FRED TONIGHT. SCATTERED MODERATE/STRONG CONVECTION IS FROM 20N-24N BETWEEN 30W- 32.5W. PLEASE SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... TROPICAL WAVE IN THE TROPICAL ATLC EXTENDS ALONG 47W FROM 9N-16N MOVING W 15-20 KT OVER THE PAST 24 HOURS. SSMI TPW DOES NOT SHOW ANY SURGE OF DEEP MOISTURE WITH NO ASSOCIATED CONVECTION. TROPICAL WAVE IN THE W CARIBBEAN EXTENDS FROM SE CUBA NEAR 19N77W TO PANAMA NEAR 9N82W MOVING W 25 KT OVER THE PAST 24 HOURS. SSMI TPW INDICATES THE WAVE IS EMBEDDED WITHIN A LOW AMPLITUDE SURGE OF DEEP MOISTURE S OF 14N. NO ASSOCIATED DEEP CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM OVER AFRICA INTO THE E TROPICAL ATLC NEAR 19N15W TO A WEAK 1012 MB LOW NEAR 12N23W CONTINUING ALONG 12N28W TO 8N49W WHERE THE ITCZ BEGINS AND CONTINUES INTO SOUTH AMERICA NEAR 6N55W. SCATTERED MODERATE/ STRONG CONVECTION IS FROM 10N-14N BETWEEN 28W-34W AND FROM 9N- 12N BETWEEN 36W-39W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 11N-13N BETWEEN 23W-25W. SCATTERED MODERATE CONVECTION IS FROM 10N-12N BETWEEN 43W-46W. ...DISCUSSION... GULF OF MEXICO... THE UPPER TROUGH HAS NARROWED CONSIDERABLY OVER THE PAST 24 HOURS AND NOW ENTERS THE GULF ACROSS THE LOUISIANA/TEXAS BORDER TO 24N94W WHERE IT MEETS AN INVERTED TROUGH THAT EXTENDS FROM E BAY OF CAMPECHE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 20N-28N BETWEEN 90W-94W. AN UPPER RIDGE DOMINATES THE REMAINDER OF THE GULF ANCHORED NEAR 27N86W. AN UPPER TROUGH IN THE NW CARIBBEAN IS GENERATING ISOLATED SHOWERS/THUNDERSTORMS DOTTING THE SE GULF S OF 26N E OF 90W. A WEAK SURFACE RIDGE COVERS THE GULF ANCHORED IN THE W ATLC. A WEAK SURFACE TROUGH IS AT 03/0300 UTC ALONG THE NW GULF COAST FROM 29N92W TO INLAND OVER TEXAS NEAR GALVESTON. THE SURFACE TROUGH WILL DISSIPATE INTO FRI. WEAK SURFACE RIDGE WILL SHIFT SLOWLY SE INTO THE E/CENTRAL GULF THROUGH SAT. CARIBBEAN SEA... AN UPPER TROUGH EXTENDS FROM THE CENTRAL ATLC ACROSS PUERTO RICO TO 17N75W THEN THROUGH AN UPPER LOW NEAR 18N83W CONTINUING TO OVER THE YUCATAN PENINSULA AND IS GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 18N TO OVER HISPANIOLA AND CUBA W OF 72W TO THE YUCATAN PENINSULA INCLUDING THE YUCATAN CHANNEL. THE MONSOON TROUGH EXTENDS FROM COLOMBIA ACROSS PANAMA AND COSTA RICA GENERATING SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS S OF LINE FROM NICARAGUA NEAR 13N84W 12N80W TO PANAMA NEAR 9N78W. THIS IS LEAVING THE E CARIBBEAN WITH CLEAR SKIES TONIGHT. FRESH TO STRONG TRADE WINDS WILL PULSE IN THE S/CENTRAL CARIBBEAN THROUGH THE SAT AS THE WEAK SURFACE RIDGE ACROSS THE W ATLC SHIFTS SLOWLY SE AND WEAKENS. THE W CARIBBEAN TROPICAL WAVE WILL MOVE ACROSS THE SW CARIBBEAN THROUGH THU NIGHT. THE NEXT TROPICAL WAVE WILL ENTER THE E CARIBBEAN SAT. ...HISPANIOLA... AN UPPER TROUGH EXTENDS FROM THE CENTRAL ATLC ACROSS PUERTO RICO TO 17N75W THEN THROUGH AN UPPER LOW NEAR 18N83W AND IS GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 18N TO OVER S HAITI W OF 72W. THE UPPER TROUGH FROM THE CENTRAL ATLC WILL GRADUALLY BECOME N/S ORIENTATED THU NIGHT GIVING THE ISLAND N FLOW ALOFT FRI AND SAT. MOISTURE WILL LINGER THROUGH EARLY THU THEN INCREASE AGAIN SAT WITH THE APPROACH OF THE NEXT TROPICAL WAVE. THIS WILL GIVE THE ISLAND A CHANCE OF AFTERNOON SHOWERS/THUNDERSTORMS FOR THU WITH AN INCREASE AGAIN ON SAT. ATLANTIC OCEAN... AN UPPER RIDGE IS ANCHORED IN THE GULF OF MEXICO EXTENDS OVER THE W ATLC TO 67W. A WEAK SURFACE RIDGE COVERS THE W ATLC WITH A 1018 MB HIGH NEAR 27N67W...A 1016 MB HIGH NEAR 19N60W...AND A SECOND 1016 MB HIGH NEAR 30N78W. AN UPPER TROUGH EXTENDS OVER THE CENTRAL ATLC N OF 27N BETWEEN 50W-67W SUPPORTING A BROAD SURFACE TROUGH THAT EXTENDS FROM 31N50W ALONG 26N54W TO 25N62W WITH ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS FROM 22N-26N BETWEEN 54W-61W. A FRONT N OF THE DISCUSSION AREA IS GENERATING SCATTERED TO NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS N OF 28N BETWEEN 60W-70W. A WEAK SURFACE RIDGE IN THE E ATLC IS BEING INTRUDED BY A T.S. FRED AND IS ANCHORED BY A 1022 MB HIGH BETWEEN THE MADEIRA AND THE AZORES. W ATLC SURFACE RIDGE WILL SHIFT SE AND GRADUALLY WEAKEN THROUGH FRI AS A WEAK TROUGH SINKS SLOWLY SE INTO THE W ATLC OFF NE FLORIDA LATE TONIGHT THROUGH FRI THEN SETTLES ALONG 28N/29N SAT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW