000 AXNT20 KNHC 132338 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST MON DEC 13 2010 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... ITCZ AXIS IS CENTERED ALONG 7N11W 5N20W 6N35W 4N44W 2N51W. CLUSTERS OF SCATTERED MODERATE TO ISOLATED STRONG CONVECTION ARE WITHIN 180 NM N OF THE ITCZ BETWEEN 20W-34W AND WITHIN 120/150 NM S OF THE ITCZ BETWEEN 23W-35W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER TROUGH CONTINUES TO MOVE OVER THE NW ATLC BUT A PORTION REMAINS OVER THE U.S. E OF THE MISSISSIPPI VALLEY SWEEPING THE GULF N OF 24N ACROSS THE FLORIDA PENINSULA INTO THE W ATLC. STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT CONTINUE TO DOMINATE THE GULF WATERS. A SURFACE RIDGE CONTINUES TO BUILD OVER THE GULF ANCHORED OVER THE CENTRAL PLAIN STATES AND WITH A 1028 MB HIGH OVER E MEXICO NEAR TAMPICO USHERING IN A VERY COOL AND DRY CONTINENTAL POLAR AIRMASS. THIS COOL DRY AIR WILL REMAIN OVER THE GULF FOR THE NEXT 24 HOURS AS S RETURN FLOW WILL INCREASE OVER THE NW GULF BY LATE TUE. CARIBBEAN SEA... A COLD FRONT ENTERS THE CARIBBEAN FROM THE W ATLC ACROSS CUBA NEAR HOLGUIN OVER THE W TIP OF JAMAICA TO INLAND OVER HONDURAS NEAR THE NICARAGUA BORDER TO OVER SOUTHERN GUATEMALA. ISOLATED SHOWERS ARE POSSIBLE WITHIN 45 NM SE OF THE FRONT AND BROKEN TO OVERCAST COLD AIR STRATOCUMULUS CLOUDS ARE OVER THE REMAINDER OF THE NW CARIBBEAN W OF THE FRONT. SW FLOW ALOFT COVERS THE NW CARIBBEAN WITH STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT THUS LIMITING ANY DEEP SHOWER ACTIVITY. A BROAD UPPER RIDGE ANCHORED IN THE W TROPICAL ATLC NEAR 8N57W DOMINATES THE REMAINDER OF THE CARIBBEAN DRAWING TROPICAL MOISTURE N OVER THE CENTRAL CARIBBEAN TO ACROSS HISPANIOLA AND PUERTO RICO WITH A SHEAR AXIS EXTENDING FROM PANAMA NEAR 9N79W ALONG 14N78W TO SW HAITI WITH DENSE LOW/MID CLOUDS AND SCATTERED SHOWERS WITHIN 90 NM EITHER SIDE OF THE SHEAR AXIS. THE E CARIBBEAN IS UNDER MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT GIVING THE AREA FAIR WEATHER THIS EVENING. ATLANTIC OCEAN... A DEEP LAYERED TROUGH CONTINUES TO MOVE OFF THE E U.S. SEABOARD AND IS SUPPORTING A STRONG COLD FRONT THAT EXTENDS INTO THE W ATLC NEAR 32N68W ALONG 26N70W ACROSS THE TURKS AND CAICOS INTO THE NW CARIBBEAN ACROSS CUBA NEAR HOLGUIN. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE WITHIN 150 NM E OF THE FRONT N OF 30N AND SCATTERED SHOWERS WITH POSSIBLE ISOLATED THUNDERSTORMS WITHIN 30 NM E OF THE REMAINDER OF THE FRONT. BROKEN TO OVERCAST COLD AIR STRATOCUMULUS CLOUDS ARE OVER THE REMAINDER OF THE W ATLC W OF THE FRONT. THE UPPER RIDGE ANCHORED IN THE W TROPICAL ATLC NEAR 8N57W EXTENDS A RIDGE AXIS JUST E OF THE LESSER ANTILLES TO BEYOND 32N59W ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 120 NM OF LINE FROM THE N COAST OF HISPANIOLA NEAR 20N70W TO 25N61W. A WEAK SURFACE TROUGH IS TO THE SE EXTENDING FROM ANTIGUA AND BARBUDA IN THE LEEWARD ISLANDS ALONG 20N60W TO 22N59W WITH ISOLATED SHOWERS POSSIBLE WITHIN 60 NM EITHER SIDE OF THE TROUGH. A SURFACE RIDGE IS OVER THE CENTRAL ATLC N OF 26N BETWEEN 41W-55W ANCHORED BY A 1030 MB HIGH OFF THE CANADIAN MARITIMES. AN UPPER LEVEL TROUGH IS OVER THE E/CENTRAL ATLC N OF 20N BETWEEN 30W-50W WITH AN UPPER RIDGE JUST TO THE E ALONG ALONG 24W. THE UPPER RIDGE IS ENHANCING SCATTERED SHOWERS N OF 29N BETWEEN 24W-35W. A WEAK COLD FRONT ENTERS THE E ATLC NEAR 32N21W EXTENDING ALONG 27N28W THEN W TO 25N42W WITH A WEAK SURFACE TROUGH TO THE S EXTENDING FROM 24N38W TO 22N42W WITH ISOLATED SHOWERS POSSIBLE WITHIN 30 NM E OF THE COLD FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW