000 AXNT20 KNHC 222334 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST TUE DEC 22 2009 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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2245 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 7N12W 3N23W 3N36W 1N50W. ISOLATED MODERATE CONVECTION IS FROM 3N-6N BETWEEN 28W-29W...AND FROM 3N-8N BETWEEN 46W-56W. ...DISCUSSION... GULF OF MEXICO... A SURFACE RIDGE CONTINUES TO DOMINATE THE GULF OF MEXICO EXTENDING FROM A HIGH PRESSURE CENTER OVER S CAROLINA. ANTI-CYCLONIC SURFACE FLOW IS ACROSS THE BASIN AROUND THE RIDGE INCREASES IN SPEED FROM E TO W...REACHING 25 KT IN THE W GULF. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH EXTENDS FROM THE BIG BEND OF FLORIDA TO THE ERN YUCATAN PENINSULA. A SWATH OF DRY AIR ALOFT IS ALONG THE UPPER TROUGH AXIS BRINGING CLEAR SKIES FROM NRN FLORIDA ACROSS THE CENTRAL GULF AND THE YUCATAN PENINSULA. MOIST SWLY FLOW AROUND THE E SIDE OF THE UPPER TROUGH IS SUPPORTING CLOUDY SKIES OVER MUCH OF S FLORIDA. EXPECT SLY RETURN FLOW TO INCREASE OVER THE WRN GULF AHEAD OF THE NEXT COLD FRONT FORECAST TO REACH THE NW WATERS LATE WED. CARIBBEAN SEA... A DYING STATIONARY FRONT DRAPES ACROSS THE CARIBBEAN FROM HISPANIOLA TO JAMAICA AND INTO THE SW CARIBBEAN TO N OF PANAMA. N-NE WINDS UP TO 25 KTS ARE BEHIND THE FRONT. MOIST SWLY FLOW ALOFT AROUND AN UPPER LEVEL RIDGE CENTERED E OF THE LESSER ANTILLES IS ACROSS THE BASIN DRAWING TROPICAL MOISTURE TO THE NE. THIS ALONG WITH SURFACE CONVERGENCE NEAR THE FRONT ARE SUPPORTING NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS FROM 13N-19N BETWEEN 72W-78W...AND OFF THE COAST OF COLOMBIA S OF 12N BETWEEN 72W-76W. SCATTERED SHOWERS ARE ALSO N OF 78W BETWEEN 70W-84W. DRY AIR AND SUBSIDENCE COVER THE FAR E CARIBBEAN E OF 67W NOTED IN WATER VAPOR IMAGERY BRINGING GENERALLY FAIR WEATHER TO THAT PORTION OF THE BASIN. MODERATE TO FRESH TRADEWINDS ARE ACROSS THE E CARIBBEAN E OF THE FRONT. EXPECT LOW PRESSURE TO FORM ALONG THE FRONTAL BOUNDARY S OF JAMAICA AS THE UPPER LEVEL TROUGH CURRENTLY OVER THE ERN GULF CONTINUES TO MOVE E INTO THE NW CARIBBEAN. ATLANTIC OCEAN... MOIST SWLY FLOW COVERS THE SW N ATLC SUPPORTING ISOLATED SHOWERS S OF 26N W OF 67W INCLUDING THE BAHAMAS. A COLD FRONT EXTENDS ACROSS MUCH OF THE CENTRAL ATLC ENTERING THE DISCUSSION AREA NW OF THE CANARY ISLANDS NEAR 32N20W CONTINUING ALONG 29N30W 25N41W 22N53W BECOMING STATIONARY TO HISPANIOLA. THE FRONT IS SUPPORTED BY A BROAD UPPER LEVEL TROUGH CENTERED OFF THE NE UNITED STATES NEAR 42N48W. STRONG WLY FLOW ALOFT AROUND THE BASE OF THIS UPPER TROUGH COVERS MUCH OF THE BASIN. SURFACE CONVERGENCE NEAR THE FRONT IS SUPPORTING NUMEROUS SHOWERS/POSSIBLE THUNDERSTORMS N OF 25N E OF 34W. ISOLATED SHOWERS ARE ALSO ALONG THE ENTIRE FRONT AXIS. GALE FORCE WINDS UP TO 35 KT ARE BEHIND THE FRONT N OF OF 27N BETWEEN 31W AND 55W. S OF THE FRONT...WEAK HIGH PRESSURE DOMINATES ANCHORED BY A 1016 MB HIGH CENTERED BETWEEN THE CAPE VERDE ISLANDS AND THE LESSER ANTILLES NEAR 17N39W. THE SURFACE HIGH IS SUPPORTED BY AN UPPER LEVEL RIDGE CENTERED E OF THE LESSER ANTILLES NEAR 13N57W EXTENDING E ACROSS THE TROPICAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE. $$ WALTON