000 AXNT20 KNHC 231142 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST SUN DEC 23 2012 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1115 UTC. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 8N13W TO 7N15W WHERE THE ITCZ CONTINUES ALONG 4N19W 4N37W TO SOUTH AMERICA NEAR 2N51W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 1N-7N BETWEEN 16W-27W AND FROM 4N-7N BETWEEN 40W-46W. CLUSTERS OF SCATTERED MODERATE CONVECTION ARE FROM 2N TO THE ITCZ BETWEEN 30W-38W. ...DISCUSSION... GULF OF MEXICO... A BROAD UPPER RIDGE EXTENDS FROM THE E PACIFIC REGION ACROSS MEXICO TO OVER THE CENTRAL CONUS COVERING THE GULF OF MEXICO WITH NW FLOW ALOFT. A SURFACE RIDGE DOMINATES THE GULF ANCHORED BY A 1025 MB HIGH S OF PENSACOLA FLORIDA NEAR 29N87W. THE SOUTHERLY RETURN FLOW OVER THE W GULF IS BANKING LOW CLOUDS WITH POSSIBLE ISOLATED SHOWERS ALONG THE NW GULF COAST FROM CORPUS CHRISTI TEXAS TO THE MISSISSIPPI/LOUISIANA BORDER. THE REMAINDER OF THE GULF IS UNDER CLEAR SKIES AGAIN THIS MORNING. HIGH PRESSURE WILL SHIFT E TODAY. A COLD FRONT WILL APPROACH THE N GULF MON THEN STALL AS A STATIONARY FRONT N OF 28N MON NIGHT AND TUE. A STRONGER COLD FRONT WILL THEN RACE SE ACROSS THE REGION TUE AND EXTEND FROM SE LOUISIANA TO S TEXAS TUE NIGHT AND FROM FLORIDA PANHANDLE TO E BAY OF CAMPECHE EARLY WED AND OUT OF THE GULF THU. CARIBBEAN SEA... THE BROAD UPPER TROUGH OVER THE W ATLC EXTENDS S OVER THE W CARIBBEAN W OF 65W SUPPORTING A COLD FRONT IN THE W ATLC THAT EXTENDS ACROSS HISPANIOLA NEAR 20N71W TO E OF JAMAICA NEAR 17N75W. A BROAD UPPER RIDGE AXIS IS E OF THE LESSER ANTILLES TO OVER THE CENTRAL ATLC COVERING THE REMAINDER OF THE E CARIBBEAN. A WEAK SURFACE TROUGH EXTENDS FROM 16N67W TO OVER NW VENEZUELA NEAR 10N71W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE E CARIBBEAN ARE WITHIN 120 NM OF LINE FROM THE VIRGIN ISLANDS NEAR 18N64W TO OFF THE COAST OF VENEZUELA NEAR 12N67W WITH ISOLATED SHOWERS OVER THE REMAINDER OF THE LESSER ANTILLES WITHIN 150 NM W OF THE SURFACE TROUGH. STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT COVER THE CARIBBEAN W OF 70W LEAVING THE REMAINDER OF THE W CARIBBEAN UNDER CLEAR SKIES THIS MORNING. STRONG NE WINDS ACROSS MUCH OF THE CARIBBEAN WILL BE CONFINED TO THE SW AND S/ CENTRAL CARIBBEAN MON THROUGH THU. ANOTHER FRONT WILL MOVE INTO THE NW CARIBBEAN THU. ATLANTIC OCEAN... THE BROAD UPPER TROUGH COVERS THE W ATLC W OF 60W SUPPORTING A COLD FRONT THAT ENTERS THE W ATLC NEAR 32N58W ALONG 25N62W INTO THE CARIBBEAN ACROSS HISPANIOLA NEAR 20N71W. ISOLATED SHOWERS ARE POSSIBLE WITHIN 90 NM W OF THE FRONT. THE SURFACE RIDGE OVER THE GULF OF MEXICO CONTINUES TO BUILD E OVER THE W ATLC W OF THE FRONT. AN UPPER TROUGH COVERS THE E ATLC N OF 10N E OF 40W SUPPORTING ANOTHER COLD FRONT THAT ENTERS THE DISCUSSION AREA NEAR 32N27W CONTINUING ALONG 24N31W TO 22N35W WHERE IT DISSIPATES TO 20N40W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 200 NM E OF THE FRONT FROM 24N-30N. W ATLC COLD FRONT WILL WEAKEN TONIGHT. HIGH PRESSURE BUILDING BEHIND THE FRONT WILL SHIFT E ALONG 30N. A STRONG COLD FRONT IS EXPECTED MOVE OFF THE NE FLORIDA COAST LATE TUE REACHING FROM 31N71W TO THE STRAITS OF FLORIDA BY LATE WED AND FROM 31N65W TO CENTRAL CUBA BY LATE THU. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW