000 AXNT20 KNHC 072345 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST WED JAN 07 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 2315 UTC. ...THE ITCZ... ITCZ IS CENTERED ALONG 7N11W 3N18W 2N30W 2N44W AND INTO NE BRAZIL NEAR 1N51W. SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS ARE FROM 3S-5N BETWEEN 3N-28N. ...DISCUSSION... GULF OF MEXICO... AT OF 2100 UTC...THE COLD FRONT HAS MOVED INTO S FLORIDA NEAR WEST PALM BEACH AND INTO THE GULF NEAR NAPLES EXTENDING SW ACROSS THE S GULF INTO THE BAY OF CAMPECHE AND ENTERING MEXICO NEAR VERACRUZ. DOPPLER RADAR INDICATES A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS ALONG THE FRONT WITH SCATTERED SHOWERS WITHIN 150 NM WNW OF THE FRONT. ISOLATED SHOWERS ARE SE AHEAD OF THE FRONT. THE UPPER LEVEL TROUGH SUPPORTING THE FRONT IS OVER THE E US COAST. BEHIND THE FRONT...SURFACE HIGH PRESSURE IS BUILDING OVER THE NW GULF BRINGING DRY AIR AND CLEAR SKIES FROM THE ERN FLORIDA PANHANDLE TO TEXAS AND N MEXICO. WINDS OF 20 TO 30 KT ARE IN THE NW GULF W OF 90W. AN UPPER LEVEL RIDGE COVERING THE W CARIBBEAN EXTENDS INTO THE SRN GULF AND SW ATLC. THE FRONT IS EXPECTED TO CONTINUE MOVING EWD AND SHOULD EXIT THE GULF LATE TONIGHT INTO THURSDAY MORNING. CARIBBEAN SEA... A MID/UPPER LEVEL RIDGE CONTINUES TO DOMINATE THE W CARIBBEAN EXTENDING N FROM AN UPPER LEVEL HIGH NEAR 14N77W ACROSS CUBA COVERING SRN PORTIONS OF THE GULF OF MEXICO AND THE SW ATLC. AN UPPER LEVEL TROUGH FROM THE CENTRAL ATLANTIC COVERS THE REMAINDER OF THE E CARIBBEAN E OF 67W. DRY AIR IN SUBSIDENCE COVERS THE ENTIRE AREA. HOWEVER...DUE TO LOW LEVEL INSTABILITY PATCHES OF LOW CLOUDS AND ISOLATED SHOWERS EXIST ACROSS THE CARIBBEAN...ESPECIALLY ALONG THE E COAST OF PANAMA AND COSTA RICA. E TO NE WINDS OF 20 TO 25 KT ARE OBSERVED ACROSS THE BASIN. THE COLD FRONT CURRENTLY IN THE GULF OF MEXICO IS EXPECTED TO ENTER THE CARIBBEAN LATE TONIGHT/THURSDAY MORNING AND THEN SLOWLY DISSIPATE THROUGH FRI. ATLANTIC OCEAN... AT OF 2100 UTC...THE COLD FRONT HAS MOVED OFF THE E COAST OF THE US ENTERING THE REGION NEAR 30N80W CROSSING FLORIDA BETWEEN WEST PALM BEACH AND NAPLES INTO THE SW GULF OF MEXICO. GALE FORCE WINDS ARE WITHIN 180 NM E OF FRONT AND N OF 29N AND ARE EXPECTED TO CONTINUE FOR THE NEXT 12 HOURS. AN UPPER RIDGE COVERING THE W CARIBBEAN EXTENDS ACROSS CUBA INTO THE SW ATLC. THE REMAINDER OF THE ATLC IS DOMINATED BY AN UPPER LEVEL TROUGH/RIDGE/TROUGH PATTERN. THE UPPER LEVEL TROUGH IS LOCATED W OF THE ANTILLES AND SUPPORTS SCATTERED SHOWER ACTIVITY FROM 10N-20N BETWEEN 28W-46W AND ISOLATED SHOWERS FROM 20N-30N BETWEEN 35W-48W. HOWEVER...THE SURFACE IS DOMINATED BY HIGH PRESSURE E OF 75W WITH A 1026 MB HIGH CENTERED NEAR 30N37W. THE COLD FRONT IS EXPECTED TO MOVE ACROSS THE W ATLC AND WEAKEN IN THE CENTRAL ATLC BY SAT. SURFACE HIGH PRESSURE IS EXPECTED TO DOMINATE THE REMAINDER OF THE BASIN OVER THE NEXT 24 HOURS. $$ WALTON/HUFFMAN