000 AXNT20 KNHC 281155 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST MON NOV 28 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 11N15W TO 9N19W. THE ITCZ CONTINUES FROM 7N20W ALONG 6N27W 6N41W TO SOUTH AMERICA NEAR 5N53W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 5N-9N E OF 7W TO THE COAST OF W AFRICA AND FROM 4N-10N BETWEEN 20W-48W. ...DISCUSSION... GULF OF MEXICO... A STRONG UPPER TROUGH DIGS S FROM THE GREAT LAKES INTO THE GULF OF MEXICO N OF 22N W OF 84W SUPPORTING A COLD FRONT THAT AT 28/0900 UTC ENTERS THE GULF OVER THE FLORIDA BIG BEND AREA ALONG 24N85W THROUGH THE YUCATAN CHANNEL INTO THE NW CARIBBEAN NEAR 21N86W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 45 NM E OF THE FRONT WITH SCATTERED SHOWERS WITHIN 200 NM W OF THE FRONT. DRY STABLE AIR CONTINUES TO MOVE OVER THE W GULF N OF 22N W OF 90W WITH CLEARING SKIES W OF LINE FROM LOUISIANA NEAR 29N92W 25N95W TO 22N96W TO TUXPAN MEXICO. A SURFACE RIDGE CONTINUES TO BUILD W OF THE FRONT WITH A 1030 MB HIGH OVER NE MEXICO. THE COLD FRONT WILL MOVE E OF THE GULF TONIGHT. SURFACE RIDGE WILL REMAIN W OF THE FRONT THROUGH THU. CARIBBEAN SEA... THE COLD FRONT FROM THE GULF OF MEXICO THAT AT 28/0900 UTC EXTENDS INTO THE NW CARIBBEAN THROUGH THE YUCATAN CHANNEL NEAR 21N86W TO INLAND OVER HONDURAS NEAR 16N87W THEN W TO THE BORDER OF GUATEMALA. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 30 NM E OF THE FRONT WITH SCATTERED SHOWERS W OF THE FRONT TO INLAND OVER THE YUCATAN PENINSULA. AN UPPER RIDGE DOMINATES THE NW CARIBBEAN W OF 78W WHILE AN UPPER TROUGH EXTENDS FROM THE CENTRAL ATLC ACROSS E CUBA AND HISPANIOLA NARROWING E OF JAMAICA NEAR 17N75W TO E PANAMA. A BROAD LOW AMPLITUDE RIDGE RESULTING IN NEAR ZONAL WESTERLY FLOW ALOFT COVERS THE REMAINDER OF THE CARIBBEAN E OF 70W. DRY STABLE AIR ALOFT AND STRONG SUBSIDENCE ARE NOTED ACROSS THE W CARIBBEAN W OF 76W AND MOST OF THE N CARIBBEAN N OF 16N BETWEEN 64W-76W. THE BROAD UPPER RIDGE IS DRAWING TROPICAL MOISTURE ACROSS THE SE CARIBBEAN WITH THE MONSOON TROUGH EXTENDING FROM COLOMBIA NEAR 12N72W 11N78W TO ACROSS COSTA RICA INTO THE E PACIFIC REGION NEAR 10N84W ARE GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 15N TO INLAND OVER COLOMBIA BETWEEN 69W-78W. A SURFACE TROUGH IS OVER THE E CARIBBEAN EXTENDING FROM THE W ATLC NEAR 22N64W THROUGH THE VIRGIN ISLANDS NEAR 18N66W TO OFF THE COAST OF VENEZUELA NEAR 12N64W WITH SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS WITHIN 120 NM OF LINE FROM 14N65W ACROSS THE LESSER ANTILLES NEAR DOMINICA TO 16N59W. THIS IS LEAVING THE REMAINDER OF THE CARIBBEAN WITH FAIR WEATHER THIS MORNING. THE COLD FRONT WILL REACH CENTRAL CUBA TO THE SW CARIBBEAN TUE WHERE IT WILL STALL AND DISSIPATE THROUGH WED. ATLANTIC OCEAN... THE SURFACE RIDGE DOMINATING MOST OF THE W ATLC EXTENDS AN AXIS THROUGH 32N72W TO THE N BAHAMA ISLANDS NEAR 26N78W AND IS RETREATING EASTWARD AHEAD OF THE APPROACHING COLD FRONT CURRENTLY IN THE GULF OF MEXICO AND CONTINUES TO GIVE THE AREA W OF 65W FAIR WEATHER THIS MORNING. AN UPPER TROUGH EXTENDS FROM THE CENTRAL ATLC NEAR 32N52W OVER THE TURKS AND CAICOS TO OVER CUBA/HISPANIOLA INTO THE CARIBBEAN SUPPORTING A LINGERING SURFACE TROUGH THAT EXTENDS THROUGH 29N53W ALONG 27N57W TO NEAR 25N61W. A BROAD HIGH AMPLITUDE UPPER RIDGE COVERS THE CENTRAL ATLC EXTENDING AN AXIS FROM AN UPPER HIGH IN THE W TROPICAL ATLC NEAR 10N50W ALONG 21N46W TO 31N45W PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 120 NM OF LINE FROM 10N54W E OF THE LESSER ANTILLES TO NEAR 19N58W...FROM 19N-25N BETWEEN 50W-64W AND WITHIN 90 NM OF LINE FROM 25N56W 29N47W TO 27N38W. A WEAKENING 1017 MB LOW IS CENTERED NEAR 31N39W. THE REMAINDER OF THE E ATLC IS DOMINATED BY A BROAD SURFACE RIDGE ANCHORED BY A 1027 MB HIGH N OF THE DISCUSSION AREA ABOUT 350 NM E OF THE AZORES PROVIDING MOSTLY FAIR WEATHER E OF 32W. A COLD FRONT WILL MOVE OFF THE E COAST OF FLORIDA TONIGHT REACHING FROM NEAR BERMUDA TO THE SE BAHAMAS LATE WED WHERE IT WILL STALL AND WEAKEN INTO A TROUGH. SURFACE RIDGE WILL BUILD IN BEHIND THE FRONT AND PREVAIL THROUGH FRI. A WEAK SURFACE LOW MAY DEVELOP NE OF THE LEEWARD ISLANDS... EMBEDDED ALONG THE SURFACE TROUGH IN THE W TROPICAL ATLC TUE AND DRIFT NE THROUGH FRI. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW