000 AXNT20 KNHC 281728 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST WED NOV 28 2012 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1645 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS WEST AFRICA TO THE COAST OF GUINEA AT 10N15W TO 10N20W. THE ITCZ BEGINS AT 10N20W AND CONTINUES ALONG 9N33W 7N45W 9N61W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 8N-12N BETWEEN 19W-25W. SIMILAR ACTIVITY IS FROM 6N-10N BETWEEN 36W-44W...AND FORM 6N-9N BETWEEN 53W-58W. ...DISCUSSION... GULF OF MEXICO... SOUTHWESTERLY FLOW ALOFT COVERS THE MAJORITY OF THE GULF OF MEXICO TODAY BETWEEN AN UPPER LEVEL RIDGE COVERING THE CARIBBEAN...EASTERN GULF...AND SW NORTH ATLC...AND AN UPPER LEVEL TROUGH WITH AXIS THROUGH CENTRAL MEXICO ALONG 100W. A BROAD UPPER LEVEL TROUGH COVERS THE NW ATLC AND THE NE CONUS SUPPORTING A COLD FRONT THAT EXTENDS FROM THE NW ATLC ACROSS CENTRAL FLORIDA AND INTO THE GULF OF MEXICO ALONG 28N81W 23N92W WHERE IT BECOMES STATIONARY ALONG 23N97W 19N96W. DUE TO THE LACK OF UPPER LEVEL SUPPORT...THE PORTION OF THE FRONT OVER THE GULF WILL BEGIN TO DISSIPATE. CURRENTLY SCATTERED SHOWERS ARE ONLY IN THE SW GULF NEAR THE STATIONARY PORTION OF THE FRONT. THE REMAINDER IS FAIRLY DRY DUE TO DRY AIR ALOFT. VISIBLE SATELLITE IMAGERY ALONG WITH SURFACE OBSERVATIONS INDICATE THAT DENSE FOG STRETCHES FROM NORTHERN FLORIDA TO THE TEXAS COAST ACROSS THE NORTHERN GULF NORTH OF 27N. THE FRONT IS EXPECTED TO DISSIPATE WITHIN 24 HOURS WITH MOISTURE REMAINING IN THE SW GULF WHICH WILL SUPPORT SHOWERS AND POSSIBLE THUNDERSTORMS. CARIBBEAN SEA... AN UPPER LEVEL RIDGE DOMINATES THE UPPER LEVELS OVER THE CARIBBEAN CENTERED OVER NORTHERN VENEZUELA AT 11N71W. MOIST SOUTHWESTERLY AND DIFFLUENT FLOW ALOFT ACROSS THE FAR WESTERN CARIBBEAN IS HELPING ENHANCE ACTIVITY NEAR A SURFACE TROUGH ALONG 21N85W TO 12N83W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 12N-21N BETWEEN 81W-88W. THE REMAINDER OF THE CARIBBEAN IS EXPERIENCING MOSTLY FAIR WEATHER DUE TO DRY AIR ALOFT WRAPPING AROUND THE EAST SIDE OF THE UPPER RIDGE. TRADEWIND FLOW OF 15-20 KT IS PRESENT ACROSS MUCH OF THE AREA WITH STRONGER WINDS OFF THE COAST OF COLOMBIA. MOIST CONDITIONS ARE EXPECTED TO REMAIN OVER THE FAR WESTERN CARIBBEAN INCLUDING CENTRAL AMERICA. ATLANTIC OCEAN... BROAD UPPER LEVEL RIDGING OVER THE NW ATLC SUPPORTS A COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N73W AND CONTINUES TO CENTRAL FLORIDA NEAR 28N81W. POSSIBLE ISOLATED SHOWERS ARE ALONG THE AXIS. THE REMAINDER OF THE SW NORTH ATLC IS UNDER MOSTLY FAIR CONDITIONS DUE TO DRY AIR ALOFT AROUND AN UPPER LEVEL RIDGE EXTENDING FROM THE CARIBBEAN. A NARROW UPPER LEVEL TROUGH...NEARLY CUT-OFF UPPER LOW...ALONG 31N50W TO 15N43W IS CAUSING SOME ACTIVE WEATHER IN THE CENTRAL ATLC. A DISSIPATING STATIONARY FRONT EXTENDS BELOW ALONG 31N42W TO 24N48W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE FROM 20N-31N BETWEEN 42W-49W. THE DISSIPATING FRONT WILL LIKELY BE ANALYZED AS A SURFACE TROUGH ON THE NEXT ANALYSIS AS IT APPEARS TO BE DRIFTING WEST. SURFACE RIDGING DOMINATES THE EASTERN ATLC ANCHORED BY A 1033 MB AZORES HIGH. THE RIDGE IS SUPPORTED BY AN UPPER LEVEL OVER THE NE ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON