000 AXNT20 KNHC 282353 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 PM 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2335 UTC. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST OF GUINEA NEAR 11N14W QUICKLY ENDING AT 8N19W. THE ITCZ CONTINUES FROM 8N19W ALONG 7N35W TO 7N53W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS WITHIN 120 NM ON EITHER SIDE OF THE ITCZ BETWEEN 23W-47W. ...DISCUSSION... GULF OF MEXICO... COLD FRONT MOVES INLAND ACROSS THE FLORIDA PENINSULA AND THE WATERS ACROSS THE STRAITS THIS EVENING. THIS FRONT IS MOVING FAIRLY QUICK INTO THE ATLC BASIN. GUSTY WNW WINDS UP TO 25 KT ARE IN ITS WAKE...GENERATING SEAS 8 TO 13 FT IN NW SWELL. THE FRONT IS LEAVING A TRAIL OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS E OF 83W ON DOPPLER RADAR IMAGERY. THIS FRONT IS SUPPORTED ALOFT BY A DEEP UPPER LEVEL TROUGH MOVING ACROSS THE EASTERN CONUS. THE REMAINDER OF THE GULF IS UNDER FAIR WEATHER CONDITIONS INFLUENCED BY VERY DRY AIR ALOFT AND STRONG SUBSIDENCE NOTICED ON WATER VAPOR IMAGERY...ESPECIALLY OVER THE FAR NE BASIN. THE FRONT IS EXPECTED TO COMPLETELY MOVE INTO THE WRN ATLC BASIN TONIGHT LEAVING A COOL AND DRY AIRMASS ACROSS THE GULF...AS SURFACE RIDGING DEVELOPS OVER THE WRN GULF OVER THE NEXT 24 HOURS. CARIBBEAN SEA... A COLD FRONT HAS ENTERED THE NW CARIBBEAN THIS AFTERNOON... CURRENTLY ANALYZED ACROSS WRN CUBA TO ERN HONDURAS ALONG 23N82W TO 15N84W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 50 NM ON EITHER SIDE OF THE FRONT. THIS FRONT IS EXPECTED TO SLOWLY MOVE EASTWARD DURING THE NEXT 24 HOURS AND START TO BECOME STATIONARY AFTER THE 24 HOURS PERIOD. DRY AIR ALOFT AND STRONG SUBSIDENCE IS AHEAD OF THE FRONT NOTED ON WATER VAPOR IMAGERY. THIS UPPER AIRMASS IS SUPPRESSING CONVECTION ACROSS MOST OF THE WRN AND NORTH CENTRAL CARIBBEAN. AN AREA OF SCATTERED SHOWERS AND THUNDERSTORMS IS IN THE SOUTH CENTRAL CARIBBEAN S OF 15N BETWEEN 67W-79W ASSOCIATED WITH THE MONSOON TROUGH EXTENDING FROM COSTA RICA TO NRN COLOMBIA. THE FAR ERN CARIBBEAN IS IMPACTED BY BROAD CYCLONIC FLOW AROUND A SURFACE TROUGH EXTENDING FROM 20N65W TO 10N66W. TOTAL PRECIPITABLE WATER IMAGERY ALSO INDICATES HIGH DEEP LAYER MOISTURE VALUES OVER THIS AREA...AS WELL AS IN THE SOUTH CENTRAL BASIN. SCATTERED SHOWERS AND THUNDERSTORMS ARE E OF 65W INCLUDING THE LESSER ANTILLES. CONDITIONS ARE EXPECTED TO SLOWLY IMPROVE OVER THE ERN CARIBBEAN FOR THE NEXT COUPLE OF DAYS AS THE SURFACE TROUGH MOVES NE OUT OF THE DISCUSSION AREA. ATLANTIC OCEAN... SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE ALREADY ENTERING THE WRN ATLC W OF 77W...AHEAD OF A COLD FRONT CURRENTLY INLAND MOVING ACROSS THE FAR SE CONUS AND FLORIDA PENINSULA. THIS FRONT IS EXPECTED TO ENTER THE ATLC TONIGHT AND CONTINUE TO TRACK EASTWARD OVER THE NEXT 24 HOURS. SURFACE RIDGING IS MAINTAINING FAIR CONDITIONS OVER THE REMAINDER OF THE W ATLC W OF 64W. AN ELONGATED UPPER LEVEL TROUGH/LOW IS CENTERED NEAR 25N62W SUPPORTS A SURFACE TROUGH ANALYZED FROM 28N53W TO 24N62W. UPPER LEVEL DIFFLUENCE E OF THE UPPER TROUGH/LOW IS SUPPORTING A SWATH OF SHOWERS AND THUNDERSTORMS WITHIN 140 NM ON EITHER SIDE OF A LINE EXTENDING FROM 30N54W TO THE ERN TROPICAL ATLC NEAR 11N56W. FARTHER E...A WEAK 1020 MB LOW IS CENTERED NEAR 30N40W CAUSING NO ACTIVE WEATHER. TO THE S OF THIS LOW...A WEAK SURFACE TROUGH IS ANALYZED FROM 27N38W TO 22N40W WITH ISOLATED SHOWERS WITHIN 20 NM ON EITHER SIDE OF THE TROUGH AXIS. THE REMAINDER OF THE ERN ATLC IS DOMINATED BY A BROAD SURFACE RIDGE AROUND A 1025 MB HIGH NE OF THE DISCUSSION AREA NEAR 37N15W PROVIDING MOSTLY FAIR WEATHER E OF 37W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ GARCIA