000 AXNT20 KNHC 010559 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 105 AM EST THU DEC 01 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0515 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA NOT REACHING THE COAST. THE ITCZ ENTERS THE E TROPICAL ATLC NEAR 12N16W EXTENDING ALONG 8N21W 8N37W TO SOUTH AMERICA NEAR 7N59W. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 3N-8N BETWEEN 17W-28W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 7N-12N BETWEEN 26W-35W. ...DISCUSSION... GULF OF MEXICO... ANOTHER UPPER TROUGH IS MOVING ACROSS THE N GULF N OF 27N WITH ZONAL WESTERLY FLOW ALOFT PREVAILING ACROSS THE REMAINDER OF THE GULF. DRY STABLE AIR AND STRONG SUBSIDENCE CONTINUES TO DOMINATE THE AREA WITH PATCHES OF SCATTERED COLD AIR STRATOCUMULUS CLOUDS OVER THE E GULF E OF 87W. CLEAR SKIES ARE OVER THE REMAINDER OF THE GULF. A SURFACE RIDGE COVERS THE GULF ANCHORED BY A 1023 MB HIGH OVER KENTUCKY. SURFACE RIDGE WILL PERSIST THROUGH SAT. A COLD FRONT WILL MOVE INTO THE NW GULF LATE SUN WITH GALE CONDITIONS EXPECTED W OF THE FRONT IN SW GULF BY LATE MON. CARIBBEAN SEA... A WEAKENING STATIONARY FRONT REMAINS EXTENDING FROM THE W ATLC INTO THE W CARIBBEAN AT 01/0300 UTC ACROSS CUBA NEAR CABO CRUZ JUST W OF JAMAICA TO THE COAST OF COSTA RICA NEAR THE PANAMA BORDER. ISOLATED SHOWERS ARE POSSIBLE S OF 15N W OF THE FRONT TO THE COAST OF NICARAGUA AND INLAND OVER COSTA RICA. AN UPPER RIDGE DOMINATES THE NW CARIBBEAN W OF 70W WHILE A NARROW UPPER TROUGH FROM THE W/CENTRAL ATLC EXTENDS S ACROSS THE VIRGIN ISLANDS TO THE ABC ISLANDS. DRY STABLE AIR ALOFT AND STRONG SUBSIDENCE COVERS ALL BUT THE FAR SE CARIBBEAN. THE MONSOON TROUGH EXTENDS ACROSS THE SW CARIBBEAN FROM COLOMBIA NEAR 10N75W ALONG 10N80W TO ACROSS PANAMA/COSTA RICA INTO THE E PACIFIC REGION NEAR 9N82W AND IS GENERATING ISOLATED SHOWERS INLAND AND WITHIN 60/75 NM ALONG THE COAST OF COLOMBIA. A SURFACE TROUGH IS JUST E OF LESSER ANTILLES BUT CONTINUES TO GENERATE ISOLATED SHOWERS E OF A LINE FROM DOMINICA ISLAND TO THE COAST OF VENEZUELA TO OVER THE WINDWARD ISLANDS. THIS IS LEAVING THE CENTRAL CARIBBEAN WITH FAIR WEATHER AGAIN TONIGHT. STATIONARY FRONT WILL DISSIPATE LATER TODAY. ATLANTIC OCEAN... AN UPPER TROUGH IS MOVING INTO THE W ATLC W OF 77W RE-INFORCING THE COLD AIR OVER THE SE CONUS. A COLD FRONT REMAINS ACROSS THE W ATLC SUPPORTED BY AN UPPER TROUGH WELL N OF THE DISCUSSION AREA AND ENTERS THE REGION AT 01/0300 UTC NEAR 32N68W ALONG 26N73W ACROSS THE S BAHAMA ISLANDS TO CUBA NEAR SAINT LUCIA WHERE IT BECOMES STATIONARY AS IT CONTINUES INTO THE CARIBBEAN. ISOLATED SHOWERS ARE WITHIN 75 NM W OF THE FRONT. A NARROWING UPPER TROUGH IS IN THE W/CENTRAL ATLC EXTENDING A AXIS FROM 32N65W SE ALONG 25N57W THEN SW ACROSS THE VIRGIN ISLANDS INTO THE CARIBBEAN SUPPORTING A SURFACE TROUGH THAT EXTENDS FROM A 1005 MB SURFACE LOW NEAR 27N60W S TO 15N60W THEN BETWEEN BARBADOS AND THE REMAINDER OF THE WINDWARD ISLANDS TO NW TRINIDAD. DRY STABLE AIR IS W OF THE SURFACE TROUGH WITH MOSTLY CLEAR SKIES BETWEEN THE SURFACE TROUGH AND THE W ATLC FRONT. A NARROW HIGH AMPLITUDE UPPER RIDGE IS TO THE E OF THE UPPER TROUGH EXTENDING AN AXIS FROM THE W TROPICAL ATLC NEAR 13N46W ALONG 26N52W TO 33N58W PROVIDING DIFFLUENCE ALOFT TO GENERATE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 90 NM OF LINE FROM THE TROPICS NEAR 8N46W 13N55W THEN N TO 20N56W. DENSE CLOUD COVER WITH POSSIBLE ISOLATED SHOWERS ARE WITHIN 150/200 NM OF LINE FROM 20N54W 28N54W TO BEYOND 32N60W. AN UPPER TROUGH DIPS S OVER THE E ATLC N OF 20N E OF 35W SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N25W TO 28N34W. SCATTERED SHOWERS ARE WITHIN 30/45 NM SE OF THE FRONT. THE REMAINDER OF THE E ATLC IS DOMINATED BY A SURFACE RIDGE ANCHORED BY A 1035 MB HIGH ABOUT 650 NM W-NW OF THE AZORES. THE WEAKENING W ATLC COLD FRONT WILL CONTINUES EASTWARD AND ABSORB THE W/CENTRAL ATLC TROUGH AS THE 1005 MB LOW WILL MOVE RAPIDLY NORTHWARD. A SURFACE RIDGE WILL BUILD BEHIND THE FRONT THROUGH SUN. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW