000 AXNT20 KNHC 251114 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST THU DEC 25 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1045 UTC. ...THE ITCZ... ITCZ IS CENTERED ALONG 8N10W 4N27W 5N456 3N52W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 4N-8N BETWEEN 39W-44W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 120 NM S OF THE ITCZ BETWEEN 10W-21W AND WITHIN 120 NM S OF THE ITCZ W OF 38W TO THE COAST OF SOUTH AMERICA. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYERED TROUGH EXTENDS FROM AN UPPER LOW MOVING INTO THE CANADIAN MARITIMES ACROSS THE NW ATLC AND E US TO OVER THE N GULF COAST STATES CLIPPING THE FAR NW GULF AS THE ACCOMPANYING COLD FRONT CONTINUES TO MOVE E EXTENDING OVER SE LOUISIANA REMAINING STATIONARY AS IT ENTERS THE GULF NEAR 30N92W RUNNING JUST OFF THE TEXAS COAST THEN INLAND NEAR BROWNSVILLE. SCATTERED SHOWERS ARE N OF 28N W OF PANAMA CITY FLORIDA AND W OF THE FRONT TO INLAND OVER TEXAS. THIS WEAK FRONT IS EXPECTED TO PUSH BACK N AS THE COLD SECTION CONTINUES TO MOVE ACROSS THE N GULF COAST STATES WITH THE NEXT MAJOR FRONT TO CROSS THE GULF ENTERING LATE SAT. THE REMAINDER OF THE GULF REMAINS UNDER AN UPPER RIDGE THAT EXTENDS FROM THE CARIBBEAN AND W ATLC WITH MODERATE/STRONG SUBSIDENCE AND DRY STABLE AIR NOTED SW OF A LINE FROM THE BIG BEND AREA OF FLORIDA TO TAMPICO MEXICO. THE SURFACE RIDGE ANCHORED WELL NE OF BERMUDA GIVES MOST OF THE GULF RETURN FLOW WITH PATCHES OF LOW CLOUDS AND ISOLATED SHOWERS MAINLY OVER THE REMAINDER OF THE GULF. CARIBBEAN SEA... THE CARIBBEAN REMAINS UNDER THE INFLUENCE OF A BROAD UPPER HIGH CENTERED IN THE W ATLC OVER THE TURKS AND CAICOS GIVING THE ENTIRE BASIN ELY UPPER FLOW WITH STRONG SUBSIDENCE AND DRY AIR. HOWEVER...SHALLOW LOW LEVEL MOISTURE CONTINUES TO STREAM ACROSS THE CARIBBEAN USHERED IN ON MODERATE/STRONG ELY TRADE WINDS WITH ISOLATED SHOWERS DOTTING THE ENTIRE CARIBBEAN. THE STRONG HIGH PRESSURE TO THE N IS EXPECTED TO CONTINUE TO SHIFT E MAINTAINING THE MODERATE/STRONG TRADE WINDS THROUGH THE WEEKEND DIMINISHING ON MON. ATLANTIC OCEAN... A COLD FRONT DRAPES ACROSS THE ATLC ENTERING THE E/CENTRAL ATLC NEAR 32N28W EXTENDING SW ALONG 26N37W THEN W TO 25N51W BECOMING STATIONARY TO 25N57W WHERE IT DISSIPATES OVER THE N AND CENTRAL BAHAMAS. BROKEN/OVERCAST LOW CLOUDS WITH ISOLATED SHOWERS ARE WITHIN 90 NM NW OF THE COLD FRONT WITH BROKEN/OVERCAST STRATOCUMULUS CLOUDS COVERING THE AREA N OF THE FRONT E OF 65W. A BROAD UPPER LEVEL RIDGE IS ANCHORED OVER THE TURKS AND CAICOS COVERING THE ENTIRE CARIBBEAN...MOST OF GULF OF MEXICO...AND THE W ATLC W OF 60W. A BROAD UPPER TROUGH ASSOCIATED WITH THE ABOVE FRONTAL BOUNDARY IS OVER THE CENTRAL ATLC EXTENDING THROUGH 32N31W THEN AS A SHEAR AXIS W ALONG 26N41W TO 22N58W. THE UPPER LEVEL TROUGH THAT COVERED THE E ATLC N OF 26N E OF 20W HAS MOVED NE OUT OF THE REGION WITH A LINGERING SURFACE TROUGH EXTENDING FROM 32N18W ACROSS THE CANARY ISLANDS TO OFF THE COAST OF WESTERN SAHARA 24N17W. A WEAK UPPER SHEAR AXIS REMAINS IN THE TROPICS EXTENDING FROM 18N45W S TO 10N48W. UPPER DIFFLUENCE E OF THIS UPPER SHEAR AXIS COUPLED WITH AN UPPER RIDGE AMPLIFIED ALONG 36W TO INLAND OVER THE W AFRICA ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 8N-14N BETWEEN 34W-46W AND DENSE CLOUD COVER WITH ISOLATED SHOWERS FROM 14N-19N FROM 35W TO OVER THE CAPE VERDE ISLANDS. MODERATE/STRONG ELY TRADE WINDS CONTINUE ACROSS THE TROPICAL ATLC AND WILL CONTINUE THROUGH THE WEEKEND. $$ WALLACE