000 AXNT20 KNHC 061745 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST SAT DEC 06 2008 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... THE ITCZ AXIS IS CENTERED ALONG 6N5W 4N20W 3N40W AND INTO NE BRAZIL NEAR 2N50W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 1N-5N BETWEEN 3W-8W AND FROM2N-6N BETWEEN 18W-27W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 3N-7N BETWEEN 31W-36W. ...DISCUSSION... GULF OF MEXICO... AS OF 1500 UTC...A QUASI-STATIONARY FRONT EXTENDS FROM THE FAR W ATLC ACROSS NRN FLORIDA NEAR FLAGLER BEACH TO CEDAR KEY AND INTO A 1019 MB LOW CENTERED NEAR 28N85W. THE FRONTAL BOUNDARY CONTINUES STATIONARY SW THROUGH 25N90W AND INTO A 1019 MB LOW IN THE WRN BAY OF CAMPECHE NEAR 21N95W. BROKEN TO OVERCAST LOW STRATUS CLOUDS ARE NORTH AND WEST OF THE FRONT ACROSS THE NW AND N/CENTRAL GULF WITH POSSIBLE ISOLATED SHOWERS ACROSS CENTRAL FLORIDA AND WITHIN 50 NM OF THE FRONT. IN THE UPPER LEVELS... BROAD TROUGHING IS OVER THE GULF WITH AXIS EXTENDING ALONG A SAVANNAH GEORGIA TO BROWNSVILLE TEXAS LINE. W-SW UPPER WINDS ARE EAST OF THE UPPER TROUGH AXIS AND ADVECTING MIDDLE TO HIGH LEVEL MOISTURE ACROSS THE MIDDLE THIRD OF THE GULF MIRRORING THE STATIONARY BOUNDARY AT THE SURFACE. ELSEWHERE...DRY AIR IN STRONG SUBSIDENCE COVERS THE SE GULF AND BAY OF CAMPECHE. CARIBBEAN SEA... MODERATE TO FRESH TRADEWINDS ARE OVER THE CARIBBEAN WITH PATCHES OF BROKEN LOW CLOUDS WITH ISOLATED SHALLOW SHOWERS PEPPERING THE BASIN. PATCHES OF THESE ISOLATED SHOWERS ARE ACROSS THE NE CARIBBEAN N OF 16N AND E OF 65W...INCLUDING THE LEEWARD ISLANDS AND ALSO IN THE SE CARIBBEAN S OF 13N AND E OF 66W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED IN THE TROPICAL ATLC NEAR 5N49W WITH A RIDGE AXIS EXTENDING NW ACROSS THE LESSER ANTILLES. BETWEEN THIS RIDGE AND THE TROUGH ACROSS THE GULF OF MEXICO SW UPPER FLOW DOMINATES ACROSS THE WRN CARIBBEAN. UPPER LEVEL MOISTURE IN THE FORM OF HIGH CLOUDINESS IS NOTED W OF 75W AND ACROSS WRN HISPANIOLA AND CUBA. STRONG SUBSIDENCE IS OVER THE REMAINDER OF THE REGION E OF 75W. ATLANTIC OCEAN... BROAD UPPER LEVEL TROUGHING IS ACROSS THE ERN CONUS AND DIPS INTO THE NRN GULF OF MEXICO WATERS. THIS UPPER FEATURE SUPPORTS A COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N74W AND TURNS QUASI-STATIONARY NEAR 31N76W SW TO FLAGLER BEACH FLORIDA. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE FRONT. A 1023 MB HIGH IS OVER THE W ATLC NEAR 34N57W AND EXTENDS A SURFACE RIDGE ACROSS BERMUDA TO NEAR 27N74W. FARTHER EAST...A 1015 MB LOW IS CENTERED OVER THE CENTRAL ATLC NEAR 27N47W WITH A SURFACE TROUGH EXTENDING TO 28N46W TO 26N45W TO 21N48W. SCATTERED SHOWERS ARE NE OF THE SURFACE TROUGH FROM 26N-32N BETWEEN 40W-45W. ANOTHER SURFACE TROUGH EXTENDS FROM 21N39W TO 14N42W. POSSIBLE ISOLATED SHOWERS COVER THE AREA FROM 15N-21N BETWEEN 39W-43W. A 1027 MB HIGH IS OVER THE E ATLC NEAR 33N17W. IN THE UPPER LEVELS...A RIDGE IS OVER THE W ATLC W OF 50W. AN UPPER LEVEL LOW IS OVER THE E ATLC NORTH OF THE DISCUSSION AREA NEAR 37N37W AND EXTENDS TROUGHING TO 18N BETWEEN 25W-45W. DIFFLUENCE E OF THE LOW IS PRODUCING SCATTERED SHOWERS FROM 27N-33N BETWEEN 15N-22N. A LARGE UPPER LEVEL HIGH IS OVER THE TROPICAL ATLC NEAR 6N24W WITH A RIDGE AXIS EXTENDING W TO 6N40W. UPPER DIFFLUENCE ASSOCIATED WITH THIS UPPER RIDGE IS SUPPORTING CONVECTION ALONG THE ITCZ AXIS. $$ HUFFMAN