000 AXNT20 KNHC 122357 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST SAT DEC 12 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. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 8N13W 2N30W TO THE EQUATOR NEAR 50W. ISOLATED MODERATE CONVECTION IS FROM 2N-6N BETWEEN 36W-44W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A STATIONARY FRONT EXTENDS ACROSS THE FLORIDA PENINSULA FROM NEAR DEERFIELD BEACH TO VENICE...AND ENTERS THE EASTERN GULF TO 29N87W WHERE IT CONTINUES WESTWARD AS A WARM FRONT ALONG THE LOUISIANA GULF COAST TO A 1014 MB LOW CENTERED NEAR FREEPORT TEXAS. A COLD FRONT EXTENDS FROM THE LOW ALONG 25N95W TO 23N98W AND INLAND ACROSS NE MEXICO. A SURFACE TROUGH IS ALSO ANALYZED FROM THE COLD FRONT NEAR 24N95W TO SOUTHERN MEXICO NEAR 18N92W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING OVER PORTIONS OF THE NW AND N/CENTRAL GULF FOCUSED MAINLY NEAR AND SOUTH OF THE WARM FRONT N OF 26N BETWEEN 87W-95W...AND ACROSS NORTHERN FLORIDA. POSSIBLE ISOLATED SHOWERS ARE WITHIN 90 NM EITHER SIDE OF THE COLD FRONT AND SURFACE TROUGH. THE LOW AND ASSOCIATED CONVECTION WITH THE FRONTAL BOUNDARIES ARE SUPPORTED ALOFT BY AN UPPER LEVEL SHORTWAVE TROUGH MOVING NE ACROSS NORTH TEXAS. MOIST SWLY FLOW...BRINGING PACIFIC MOISTURE ACROSS MEXICO AND THE NORTHERN GULF IS ALSO PROVIDING AN UPPER LEVEL DIFFLUENT ENVIRONMENT BETWEEN THE UPPER LEVEL TROUGH AND A BROAD UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED OVER THE WESTERN CARIBBEAN. THE REMAINDER OF THE GULF REMAINS UNDER GENERALLY FAIR SKIES AND S-SE SURFACE WINDS UP TO 25 KT. CARIBBEAN SEA... AN UPPER LEVEL RIDGE IS CENTERED OVER THE WESTERN CARIBBEAN NEAR 17N78W WITH STRONG SUBSIDENCE AND DRY AIR NOTED ON WATER VAPOR IMAGERY COVERING MUCH OF THE CARIBBEAN SEA AND CENTRAL AMERICA. MOSTLY FAIR WEATHER CONTINUES ACROSS THE BASIN WITH MODERATE TO STRONG EASTERLY TRADES EXPECTED TO PERSIST THROUGH EARLY WEDNESDAY. HOWEVER...A FEW AREAS OF ISOLATED LOW-LEVEL SHOWERS ARE OCCURRING ACROSS THE NW CARIBBEAN FROM 16N-21N BETWEEN 83W-88W AND OVER THE EASTERN CARIBBEAN E OF 72W. ATLANTIC OCEAN... A COLD FRONT ENTERS THE CENTRAL ATLC NEAR 32N47W AND EXTENDS SW INTO THE SW NORTH ATLC ALONG 26N60W TO 25N70W WHERE IT CONTINUES WESTWARD AS A STATIONARY FRONT TO DEERFIELD BEACH FLORIDA. ISOLATED SHOWERS ARE WITHIN 60 NM EITHER SIDE OF THE COLD FRONT AND WITHIN 90 NM NORTH OF THE STATIONARY FRONT. LINGERING ISOLATED SHOWERS FOLLOW NW OF THE FRONT W OF 70W ACROSS THE REMAINDER OF THE W ATLC AS A SURFACE RIDGE BUILDS IN N OF 26N W OF 60W ANCHORED ON A 1037 MB HIGH CENTERED OVER SE VIRGINIA. THE COLD FRONT IS SUPPORTED ALOFT BY AN UPPER LEVEL LONGWAVE TROUGH LOCATED WELL NORTH OF THE AREA ACROSS THE NW NORTH ATLC. FARTHER EAST...ACROSS THE REMAINDER OF THE CENTRAL ATLC AND EASTERN ATLC...A BROAD SURFACE RIDGE IS IN PLACE ANCHORED BY A 1021 MB HIGH CENTERED NEAR 25N38W BRINGING GENERALLY FAIR WEATHER E OF 50W. $$ HUFFMAN