000 AXNT20 KNHC 271159 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT JUL 27 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1122 UTC. ...SPECIAL FEATURE... TROPICAL STORM DORIAN IS CENTERED NEAR 18.2N 50.0W AT 27/0900 UTC OR ABOUT 750 NM E OF THE NORTHERN LEEWARD ISLANDS MOVING W AT 19 KT. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. MINIMUM CENTRAL PRESSURE IS 1011 MB. PLEASE SEE THE LATEST FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC AND THE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/WTNT34 KNHC FOR MORE DETAILS. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 17N-20N BETWEEN 48W-52W. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS OVER THE CAPE VERDE ISLANDS FROM 18N23W TO 6N25W MOVING W 15 KT. THE SURGE OF DEEP MOISTURE IS TRAILING THE WAVE WITH A MODERATE SURGE ALONG THE WAVE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY WITH NO ASSOCIATED DEEP CONVECTION. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 20N16W AND CONTINUES ALONG 12N23W TO 7N36W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 6N49W TO SOUTH AMERICA NEAR 7N58W. CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE FROM 8N-12N E OF THE MONSOON TROUGH TO THE COAST OF W AFRICA. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE WITHIN 90 NM S OF THE MONSOON TROUGH BETWEEN 25W-32W AND WITHIN 90 NM N OF THE MONSOON TROUGH BETWEEN 32W-36W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE EXTENDS ACROSS TEXAS INTO THE GULF THEN TO OVER FLORIDA GIVING THE GULF MOSTLY NORTHERLY FLOW ALOFT. AN UPPER LOW IS OVER S MEXICO AND THE BAY OF CAMPECHE GENERATING SCATTERED SHOWERS INLAND OVER S MEXICO. AN UPPER TROUGH IS OVER THE E CONUS SUPPORTING A FRONTAL SYSTEM INLAND OVER LOUISIANA AND TEXAS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS INLAND WITH POSSIBLE ISOLATED SHOWERS MOVING OVER THE FAR NW GULF WITHIN 60 NM ALONG THE S COAST OF LOUISIANA. A WEAK SURFACE RIDGE DOMINATES THE GULF EXTENDING FROM THE W ATLC ACROSS S FLORIDA TO THE COAST OF MEXICO WITH A 1018 MB HIGH NEAR 24N88W LEAVING THE REMAINDER OF THE GULF WITH MOSTLY CLEAR SKIES THIS MORNING. SURFACE RIDGE WILL PREVAIL ACROSS THE GULF THROUGH WED. CARIBBEAN SEA... AN UPPER RIDGE COVERS THE W CARIBBEAN W OF 74W ANCHORED ALONG THE COAST OF NICARAGUA. THE UPPER LOW OVER THE W ATLC EXTENDS S OVER THE E CARIBBEAN INCLUDING THE N CARIBBEAN ISLANDS FROM THE LEEWARD ISLANDS TO E CUBA GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS N OF 16N BETWEEN 62W-71W...N OF 18N TO THE COAST OF CUBA BETWEEN 75W-80W...AND AT THE BASE OF THE UPPER TROUGH WITHIN 90 NM ALONG THE COAST OF VENEZUELA BETWEEN 64W-70W. THE MONSOON TROUGH EXTENDS ALONG 9N/10N FROM COLOMBIA ACROSS PANAMA/COSTA RICA INTO THE E PACIFIC REGION GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 11N W OF 75W. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN UNDER MOSTLY CLEAR SKIES THIS MORNING. TROPICAL STORM DORIAN IS EXPECTED TO WEAKEN INTO A REMNANT LOW BY THE TIME IT MOVES N OF PUERTO RICO ON MON. FRESH TO STRONG E WINDS WILL CONTINUE ACROSS MOST OF THE CENTRAL CARIBBEAN WITH HIGHEST WINDS NEAR THE COAST OF COLOMBIA. HISPANIOLA... CURRENTLY SKIES ARE CLEAR ACROSS MOST OF HISPANIOLA WITH THE EXCEPTION OF THE EASTERN TIP OF THE DOMINICAN REPUBLIC WHERE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE CONTINUING. THIS ACTIVITY IS DUE TO THE UPPER TROUGH THAT EXTENDS FROM THE W ATLC OVER THE E CARIBBEAN. AFTERNOON SHOWERS AND THUNDERSTORMS ARE POSSIBLE WITH DAYTIME HEATING AND WILL BE ENHANCED BY THE UPPER TROUGH THAT WILL PERSIST THROUGH WED. TROPICAL STORM DORIAN IS EXPECTED TO WEAKEN INTO A REMNANT LOW BY THE TIME IT MOVES N OF PUERTO RICO ON MON. PRECIPITATION COULD INCREASE AS THE REMNANTS OF TROPICAL STORM DORIAN MOVE RAPIDLY W-NW N OF THE ISLAND AS A STRONG TROPICAL WAVE THEN THROUGH THE SOUTHERN BAHAMAS THROUGH WED. ATLANTIC OCEAN... AN UPPER TROUGH DIPS S OVER THE FAR W ATLC N OF 27N W OF 72W TO OVER NE FLORIDA SUPPORTING A STATIONARY FRONT THAT AT 27/0900 UTC EXTENDS FROM A WEAK 1014 MB LOW NEAR 33N74W ALONG 30N76W TO A 1013 MB LOW NEAR 28N79W CONTINUING TO OVER S FLORIDA NEAR FORT PIERCE. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 90 NM E OF THE FRONT/LOWS. AN ELONGATED UPPER LOW IS OVER THE W/CENTRAL ATLC CENTERED NEAR 24N67W COVERING THE AREA BETWEEN 58W-72W AND EXTENDING S OVER THE E CARIBBEAN GENERATING CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER A BROAD AREA FROM 20N-33N BETWEEN 50W-70W. A SURFACE RIDGE DOMINATES THE CENTRAL ATLC N OF 20N BETWEEN 30W-70W WITH A WEAK RIDGE AXIS EXTENDING W OVER THE GULF OF MEXICO AND ANCHORED BY A 1032 MB HIGH W OF THE AZORES. AN UPPER TROUGH IS OVER THE NE ATLC N OF THE DISCUSSION AREA SUPPORTING A WEAK SURFACE TROUGH THAT EXTENDS FROM 31N22W TO 27N29W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 45 NM EITHER SIDE OF THE TROUGH. SURFACE RIDGE WILL PERSIST THROUGH WED WHILE REMNANTS OF TROPICAL STORM DORIAN MOVE RAPIDLY W-NW S OF THE RIDGE AS A STRONG TROPICAL WAVE THROUGH THE SOUTHERN BAHAMAS SUN NIGHT THROUGH WED. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW