000 AXNT20 KNHC 022340 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED NOV 02 2011 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 13N43W TO 5N49W MOVING W NEAR 15 KT. WAVE REMAINS EMBEDDED DEEP LAYER MOISTURE THAT ENCOMPASSES THE MONSOON TROUGH/ITCZ ACROSS THE TROPICAL ATLC. WAVE IS WELL DEFINED IN THE GFS STREAMLINES WITH BROAD CYCLONIC TURNING OBSERVED ON SATELLITE IMAGERY. SCATTERED MODERATE WITH EMBEDDED CLUSTERS OF ISOLATED STRONG CONVECTION COVERS THE AREA FROM 6N-12N BETWEEN 45W-51W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 12N16W TO 9N19W. THE ITCZ AXIS EXTENDS FROM 9N19W ALONG 5N31W TO 5N44W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 2N-10N BETWEEN 24W-36W AND FROM 12N-15N BETWEEN 40W-49W. ...DISCUSSION... GULF OF MEXICO... AN UPPER RIDGE COVERS THE GULF ANCHORED OVER N GUATEMALA EXTENDING A RIDGE AXIS N TO OVER THE SE CONUS. DRY STABLE AIR ALOFT DOMINATES THE GULF. A STRONG SURFACE RIDGE ALSO DOMINATES THE MOST OF THE GULF ANCHORED BY A 1029 MB HIGH OVER NORTH CAROLINA. THE EXCEPTION IS OVER THE BAY OF CAMPECHE WHERE A SURFACE TROUGH EXTENDS FROM THE COAST OF MEXICO NEAR THE ISTHMUS OF TEHUANTEPEC TO 22N96W GENERATING SCATTERED LOW LEVEL SHOWERS WITHIN 75 NM EITHER SIDE OF THE TROUGH AXIS. THIS IS LEAVING THE REMAINDER OF THE GULF UNDER MOSTLY FAIR WEATHER THIS EVENING. A COLD FRONT WILL ENTER THE NW GULF EARLY THU AND WILL REACH FROM THE W FLORIDA PENINSULA TO NEAR TUXPAN MEXICO THU EVENING THEN WEAKEN FROM S FLORIDA TO THE CENTRAL BAY OF CAMPECHE FRI EVENING AND DISSIPATE BY SAT EVENING. CARIBBEAN SEA... THE BROAD UPPER RIDGE COVERING THE GULF OF MEXICO COVERS THE NW CARIBBEAN W OF 75W AND IS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 17N-20N W OF 80W TO INLAND OVER THE YUCATAN PENINSULA. A SECOND BROAD UPPER RIDGE EXTENDS OVER THE E CARIBBEAN FROM THE TROPICAL ATLC INDUCING AN INVERTED UPPER TROUGH THAT EXTENDS FROM E PANAMA NEAR 9N78W TO HISPANIOLA NEAR THE HAITI/DOMINICAN REPUBLIC BORDER. A SURFACE TROUGH EXTENDS FROM 17N85W ACROSS NE HONDURAS/NICARAGUA TO 11N83W GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60 NM E AND 90 NM W OF THE TROUGH AXIS TO INLAND OVER NICARAGUA. THE UPPER RIDGE OVER THE E CARIBBEAN IS PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS/THUNDERSTORMS N OF 14N E OF 71W TO OVER THE ISLANDS FROM HISPANIOLA TO THE LEEWARD ISLANDS. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN UNDER FAIR WEATHER THIS EVENING. THE TROPICAL WAVE WILL REACH THE E CARIBBEAN FRI NIGHT INTO SAT. ATLANTIC OCEAN... A BROAD UPPER TROUGH AXIS ENTERS THE W ATLC NEAR 32N72W TO OVER THE N BAHAMA ISLANDS NEAR 23N78W SUPPORTING A COLD FRONT THAT ENTERS THE W/CENTRAL ATLC NEAR 32N62W ALONG 27N67W TO 24N73W WHERE A SHEAR AXIS CONTINUES ACROSS THE CENTRAL BAHAMA ISLANDS TO 23N79W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 45 NM OF THE FRONT/SHEAR AXIS W OF 68W. A SURFACE TROUGH IS TO THE E EXTENDING FROM 27N63W TO OVER THE MONA PASSAGE WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 60W TO THE SURFACE TROUGH. A LARGE UPPER RIDGE COVERS MOST OF THE REMAINDER OF THE ATLC WATERS WITH THE EXCEPTION OF AN UPPER TROUGH EXTENDING FROM 29N56W TO AN UPPER LOW NEAR 24N54W GENERATING SCATTERED SHOWERS/ THUNDERSTORMS WITHIN 60 NM OF LINE FROM 27N56W TO 32N57W AND CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 20N-25N BETWEEN 49W-59W. AN UPPER TROUGH DIPS INTO THE E ATLC TO 30N E OF 20W SUPPORTING A WEAK COLD FRONT THAT ENTERS THE REGION NEAR 32N16W ALONG 26N34W TO 27N41W. A BROAD SURFACE RIDGE DOMINATES THE REMAINDER OF THE CENTRAL ATLC AND THE E ATLC N OF 20N E OF 60W ANCHORED BY A 1024 MB HIGH JUST N OF THE REGION NEAR 34N43W AND BISECTED BY THE ABOVE COLD FRONT. THE W ATLC COLD FRONT AND SURFACE TROUGH WILL MERGE AS IT MOVES INTO THE CENTRAL ATLC BY THU NIGHT. A NEW COLD FRONT IS EXPECTED TO MOVE ACROSS THE W ATLC FRI INTO SAT WEAKENING BY SUN NIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW