000 AXNT20 KNHC 301131 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST TUE DEC 30 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1130 UTC. ...THE ITCZ... THE ITCZ AXIS IS ANALYZED FROM THE NORTHERN COAST OF LIBERIA NEAR 6N11W TO 4.5N20W 4N30W 3N40W TO NORTHEASTERN BRAZIL NEAR THE CITY OF MAPACA AT 1N50W. SATELLITE IMAGERY SHOWS MODERATE TO STRONG CONVECTION 100 NM NORTH OF THE ITCZ BETWEEN 46W AND 50W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL TROUGH COVERING MUCH OF THE CENTRAL UNITED STATES PREPARES TO ENTER THE NORTHWEST GULF OF MEXICO THIS MORNING. LIGHT SOUTHWEST FLOW ALOFT RELATED TO THIS UPPER TROUGH IS BRINGING MID TO UPPER LEVEL MOISTURE ACROSS THE BASIN. A SURFACE TROUGH IS ANALYZED ALONG THE SOUTHERN TEXAS COAST NEAR CORPUS CHRISTI DOWN TO PAPAMTIA MEXICO. A WEAK SURFACE LOW OF 1018 MB HAS DEVELOPED ON THE NORTHERN TIP OF THIS SURFACE TROUGH NEAR 27N95W. DOPPLER RADAR IMAGERY SHOWS MODERATE TO HEAVY SHOWERS MOVING NORTHEASTWARD ALONG THE TEXAS COAST TO LOUISIANA COAST. SHIP AND BUOY OBSERVATIONS DISPLAY EASTERLY WINDS 10 TO 15 KTS ACROSS THE BASIN...EXCEPT FOR CYCLONIC ROTATION AROUND THE SURFACE LOW. COMPUTER MODELS SHOW THIS TROUGH SWINGING NORTH OF THE GULF...WHILE MOVING THE SURFACE LOW ALONG THE NORTHERN GULF COAST. THEREFORE...CONVECTION IS MORE LIKELY TO REMAIN ON THE NORTHERN HALF OF THE BASIN NORTH OF 24N. THE CARIBBEAN SEA... AN UPPER LEVEL RIDGE OF HIGH PRESSURE COVERS MOST OF THE CARIBBEAN BASIN FROM THE LESSER ANTILLES TO 81W...SUPPRESSING DEEP CONVECTION IN THIS REGION. WATER VAPOR IMAGERY SHOWS STRONG SUBSIDENCE OF AIR OVER THE EAST AND CENTRAL BASIN...AND SOME MID TO UPPER LEVEL MOISTURE MOVING INTO THE NNW BASIN. INFRA-RED IMAGERY SHOWS AND AREA OF WEAK CONVECTION FROM 16N TO 20N BETWEEN 85W AND 88W. ANOTHER AREA OF SHOWERS IS FOUND OVER THE NE BASIN NEAR PUERTO RICO. DOPPLER RADAR IMAGERY SHOWS A CLUSTER OF MODERATE TO HEAVY SHOWERS MOVING SOUTH ACROSS THE ISLAND OF PUERTO RICO. THESE SHOWERS ARE RELATED TO THE TAIL END OF A COLD FRONT MOVING 50 NM NORTH OF SAN JUAN. CONDITIONS WILL SLOWLY IMPROVE OVER THE NEXT 24 HOURS IN THIS AREA...AS COLD FRONT CONTINUES ITS CRUISE EASTWARD INTO THE CENTRAL ATLANTIC OCEAN. SHIP AND BUOY OBSERVATIONS SHOW EASTERLY WINDS 10 TO 15 KT ACROSS THE BASIN. COMPUTER MODELS KEEP HIGH PRESSURE WEATHER ACROSS THE BASIN FOR THE NEXT FEW DAYS. THE ATLANTIC OCEAN... A COLD FRONT IS ANALYZED OVER THE WEST/CENTRAL ATLANTIC ALONG 30N50W TO 23N55W TO NORTH OF THE ISLAND OF PUERTO RICO. THIS FRONT WILL BE OVER THE CENTRAL ATLANTIC IN THE NEXT 12 HOURS. WEAK CONVECTION IS SEEN 50 NM EAST OF THIS FRONT COVERING AN AREA FROM 23N TO 32N BETWEEN 47W AND 53W. GALE FORCE WINDS WILL CONTINUE TO DEVELOP NORTH OF 28N WITHIN 300 NM EAST OF THE FRONT OVER THE NEXT 24 HOURS. A SURFACE 1025 MB HIGH IS FOUND OVER THE CENTRAL ATLANTIC NEAR 30N35W. THIS HIGH PRESSURE WILL SLOWLY DISSIPATE AS IT MOVES TO THE EAST. ANOTHER COLD FRONT IS FOUND OVER THE EASTERN ATLANTIC ENTERING TO NORTHWEST AFRICA. THIS TROUGH IS DISSIPATING AS IT ENTERS THE NORTH AFRICAN REGION. LOOK FOR THE WESTERN ATLANTIC FRONT TO SLOWLY WEAKEN...BECOMING ALMOST STATIONARY...WITH SHOWERS WITHIN 250 NM ON EITHER SIDE OF THE FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE. $$ GARCIA