000 AXNT20 KNHC 050602 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU SEP 05 2013 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 FEATURE... TROPICAL DEPRESSION SEVEN WAS UPGRADED TO TROPICAL STORM GABRIELLE AT 05/0300 UTC. TROPICAL STORM GABRIELLE IS CENTERED NEAR 17.3N 66.8W AT 05/0600 UTC OR ABOUT 45 NM S-SW OF PONCE PUERTO RICO AND ABOUT 120 NM SE OF PUNTA CANA DOMINICAN REPUBLIC MOVING NW AT 7 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. SEE THE LATEST INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT2/WTNT32 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT2/WTNT22 KNHC FOR MORE DETAILS. GABRIELLE IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF 3 TO 6 INCHES OVER PORTIONS OF PUERTO RICO...THE U.S. VIRGIN ISLANDS...AND EASTERN PORTIONS OF THE DOMINICAN REPUBLIC WITH ISOLATED MAXIMUM AMOUNTS OF UP TO 10 INCHES POSSIBLE IN AREAS OF MOUNTAINOUS TERRAIN. THESE HEAVIER AMOUNTS COULD RESULT IN DANGEROUS FLASH FLOODS AND MUD SLIDES OVER MOUNTAINOUS TERRAIN. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 16N-19N BETWEEN 64W- 67W INCLUDING THE VIRGIN ISLANDS AND PUERTO RICO. ...TROPICAL WAVES... TROPICAL WAVE W OF THE CAPE VERDE ISLANDS EXTENDS FROM 19N27W THROUGH A 1012 MB LOW NEAR 13N30W TO 8N30W. WAVE HAS BEEN MOVING W NEAR 10-15 KT FOR THE PAST 24 HOURS. WAVE IS EMBEDDED WITHIN A BROAD SURGE OF DEEP MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 60 NM OF LINE FROM 17N27W 16N30W TO 13N31W. TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC EXTENDS FROM 21N49W TO 11N47W. WAVE HAS BEEN MOVING W 15-20 KT FOR THE PAST 24 HOURS. WAVE IS EMBEDDED WITHIN A NARROW SURGE OF DEEP MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE CONVECTION IS WITHIN 90 NM W OF THE WAVE BETWEEN 15N- 18N. TROPICAL WAVE APPROACHING THE LESSER ANTILLES EXTENDS FROM 21N62W TO 12N60W. WAVE HAS BEEN MOVING W NEAR 10 KT FOR THE PAST 24 HOURS. WAVE IS EMBEDDED WITHIN A BROAD AREA OF DEEP MOISTURE AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE TO STRONG CONVECTION IS FROM 17N-22N BETWEEN 57W-63W WITH CLUSTERS OF SIMILAR CONVECTION FROM 14N-17N BETWEEN 57W- 64W. THE UPPER RIDGE OVER TROPICAL STORM GABRIELLE IS ENHANCING THE ACTIVITY ASSOCIATED WITH THIS WAVE. TROPICAL WAVE IN THE W CARIBBEAN EXTENDS FROM CUBA NEAR 21N78W TO 10N77W. WAVE HAS BEEN MOVING NEAR 10 KT FOR THE PAST 24 HOURS. WAVE IS EMBEDDED WITHIN AN AREA OF MODERATE TO DEEP MOISTURE THAT COVERS THE CARIBBEAN AS DEPICTED ON TOTAL PRECIPITABLE WATER IMAGERY. NO ASSOCIATED SHOWERS OR CONVECTION. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 15N17W AND CONTINUES ALONG 13N22W THROUGH THE LOW/TROPICAL WAVE NEAR 13N30W ALONG 10N34W TO 9N39W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 9N47W TO 13N55W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS INLAND AND WITHIN 90 NM ALONG THE COAST OF AFRICA BETWEEN GUINEA BISSAU AND 17N IN MAURITANIA. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE IS ANCHORED OVER S/CENTRAL MEXICO AND EXTENDS AN AXIS ACROSS VERACRUZ TO OVER THE GULF TO S FLORIDA. A SURFACE TROUGH IS BENEATH THIS UPPER RIDGE EXTENDING AT 05/0300 UTC FROM 24N93W TO A 1012 MB LOW ALONG THE COAST OF MEXICO NEAR 19N91W. DEEP MOISTURE COVERS MOST OF THE GULF AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...ONLY ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE DOTTING THE AREA S OF 27N FROM FLORIDA TO OVER MEXICO AND THE YUCATAN. A BROAD UPPER TROUGH COVERS THE NE GULF AND INTO THE W ATLC SUPPORTING A STATIONARY BOUNDARY THAT REMAINS INLAND OVER THE SE CONUS. THE LOW/SURFACE TROUGH WILL PREVAIL ACROSS THE BAY OF CAMPECHE AND SW GULF THROUGH MON. CARIBBEAN SEA... PRIMARY CONCERN TONIGHT IS TROPICAL STORM GABRIELLE AND THE ACCOMPANYING RAINFALL. SEE SPECIAL FEATURES ABOVE. THE UPPER RIDGE OVER THE GULF OF MEXICO COVERS THE NW CARIBBEAN N OF 15N W OF 81W. THE UPPER RIDGE ASSOCIATED WITH TROPICAL STORM GABRIELLE DOMINATES THE E CARIBBEAN E OF 77W. THIS IS INDUCING AN INVERTED TROUGH THAT EXTENDS FROM COSTA RICA TO OVER CUBA NEAR 21N78W. SOME ISOLATED SHOWERS/THUNDERSTORMS DOT THE N CARIBBEAN N OF 18N BETWEEN 75W-82W. THE MONSOON TROUGH EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 8N77W TO ACROSS COSTA RICA NEAR 11N84W. THE ACTIVITY OVER THE E CARIBBEAN IS DUE TO EITHER TROPICAL STORM GABRIELLE OR THE TROPICAL WAVE APPROACHING THE LESSER ANTILLES. GABRIELLE IS EXPECTED TO MOVE THROUGH THE MONA PASSAGE LATE THU/EARLY FRI. HISPANIOLA... SATELLITE IMAGERY INDICATES LOW LEVEL CLOUDS WITH POSSIBLE ISOLATED SHOWERS ARE ACROSS THE ISLAND TONIGHT. TROPICAL STORM GABRIELLE IS EXPECTED TO MOVE THROUGH THE MONA PASSAGE LATE THU/EARLY FRI GIVING THE DOMINICAN REPUBLIC MOST OF THE HEAVY RAINFALL. THE TROPICAL WAVE APPROACHING THE LESSER ANTILLES TONIGHT IS EXPECTED TO CONTINUE MOVING W IN WAKE OF GABRIELLE. THIS COULD BRING EVEN MORE RAIN TO THE DOMINICAN REPUBLIC AND CONTINUING TO SHIFT W OVER HAITI FRI INTO SAT. GABRIELLE IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF 3 TO 6 INCHES OVER THE EASTERN PORTIONS OF THE DOMINICAN REPUBLIC WITH ISOLATED MAXIMUM AMOUNTS OF UP TO 10 INCHES POSSIBLE IN AREAS OF MOUNTAINOUS TERRAIN. THESE HEAVIER AMOUNTS COULD RESULT IN DANGEROUS FLASH FLOODS AND MUD SLIDES OVER MOUNTAINOUS TERRAIN. ATLANTIC OCEAN... THE UPPER TROUGH OVER THE NE GULF OF MEXICO EXTENDS OVER THE FAR W ATLC N OF 28N W OF 70W SUPPORTING A FRONTAL BOUNDARY THAT IS N OF THE DISCUSSION AREA. ISOLATED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE S OF 27W W OF 77W. AN UPPER LOW COVERS THE REMAINDER OF THE W ATLC INTO THE CENTRAL ATLC N OF 24N CENTERED NEAR 28N61W. A SECOND WEAKER UPPER LOW IS CENTERED NEAR 24N45W. THE UPPER RIDGE ASSOCIATED WITH TROPICAL STORM GABRIELLE EXTENDS AN UPPER AXIS NE ALONG 22N56W TO 31N51W WHICH IS PROVIDING DIFFLUENCE ALOFT TO GENERATE AN AREA OF SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS WITHIN 60 NM OF LINE FROM 25N51W TO 27N54W WITH ISOLATED SHOWERS FROM 24N-32N BETWEEN 54W-60W. THE REMAINDER OF THE ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1025 MB HIGH NEAR 34N51W AND A 1025 MB HIGH NEAR 33N32W. TROPICAL STORM GABRIELLE IS EXPECTED TO MOVE INTO THE W ATLC THROUGH THE MONA PASSAGE LATE THU/EARLY FRI CONTINUING TO MOVE NORTHWARD E OF THE TURKS AND CAICOS BEFORE NE ON SUN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW