000 AXNT20 KNHC 241116 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST WED DEC 24 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 7N9W 5N20W 5N45W 3N53W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM N OF THE ITCZ FROM 23W-26W AND AND WITHIN 175 NM N OF THE ITCZ FROM 33W-36W. SCATTERED MODERATE IS WITHIN 60 NM OF 1N FROM 41W-43W. ...DISCUSSION... GULF OF MEXICO... A DEEP LAYERED TROUGH EXTENDS FROM THE THE CENTRAL US TO OVER TEXAS AND N MEXICO WITH THE ACCOMPANYING COMPLEX FRONTAL SYSTEM REMAINING WELL INLAND. THIS WEAK FRONT IS EXPECTED TO ENTER THE NW GULF LATE TODAY PULLING N ACROSS THE N GULF COAST WITH THE NEXT MAJOR FRONT TO CROSS THE GULF ENTERING LATE SAT. AN UPPER RIDGE EXTENDS OVER THE GULF FROM THE CARIBBEAN WITH MODERATE/ STRONG SUBSIDENCE AND DRY STABLE AIR NOTED ACROSS THE GULF WATERS MAINLY S OF 27N. THE SURFACE RIDGE COVERS THE GULF ANCHORED WELL N OF BERMUDA WITH RETURN FLOW OVER THE ENTIRE GULF BASIN. PATCHES OF LOW CLOUDS WITH ISOLATED SHOWERS ARE N OF 23N E OF 90W TO INLAND THE NE GULF COAST STATES INCLUDING THE FLORIDA PENINSULA AND WITHIN 75 NM ALONG THE COAST OF TEXAS AND EXTREME W LOUISIANA. OTHERWISE THE REMAINDER OF THE GULF REMAINS TRANQUIL THIS MORNING. CARIBBEAN SEA... THE CARIBBEAN REMAINS UNDER THE INFLUENCE OF A BROAD UPPER HIGH CENTERED BETWEEN THE ABC ISLANDS AND HISPANIOLA ENCOMPASSING THE ENTIRE CARIBBEAN BASIN WITH STRONG SUBSIDENCE AND DRY AIR. THIS UPPER LEVEL FEATURE ALSO ENVELOPS CENTRAL AMERICA AND THE N PORTION OF SOUTH AMERICA INTO THE W TROPICAL ATLC. HOWEVER... SHALLOW LOW LEVEL MOISTURE CONTINUES TO STREAM ACROSS THE BASIN USHERED IN ON STRONG ELY TRADE WINDS WITH ISOLATED SHOWERS DOTTING MOST OF THE ENTIRE CARIBBEAN INCLUDING THE LESSER ANTILLES. THE STRONG HIGH PRESSURE TO THE N IS SHIFTING E MAINTAINING THE STRONG TRADE WINDS THROUGH THE WEEKEND. ATLANTIC OCEAN... A COLD FRONT ENTERS THE W/CENTRAL ATLC NEAR 32N44W EXTENDING SW TO 26N56W BECOMING STATIONARY TO 24N67W WHERE IT DISSIPATES ACROSS THE CENTRAL BAHAMAS TO NEAR 23N77W. BROKEN/OVERCAST LOW CLOUDS WITH ISOLATED SHOWERS ARE WITHIN 90 NM NW OF THE COLD FRONT WITH BROKEN/OVERCAST COLD AIR STRATOCUMULUS CLOUDS COVERING THE REMAINDER OF THE AREA N OF THE ENTIRE FRONT. A BROAD UPPER LEVEL RIDGE EXTENDS FROM THE CARIBBEAN WITH AXIS ACROSS PUERTO RICO NE TO BEYOND 25N41W. AN UPPER LEVEL LOW COVERS THE E ATLC N OF 21N E OF 29W TO THE COAST OF W AFRICA AND CENTERED NEAR 32N21W WITH A 1009 MB SURFACE LOW CENTERED NEAR 32N22W AND A COLD FRONT ENTERING THE AREA NEAR 32N18W TO 29N20W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE N OF 28N FROM OVER THE CANARY ISLANDS TO 20W. A UPPER SHEAR AXIS EXTENDS FROM THE UPPER LOW NEAR 23N26W WSW INTO THE TROPICS ALONG 18N35W TO 8N58W. UPPER DIFFLUENCE SE OF THIS UPPER LOW/SHEAR AXIS COUPLED WITH AN UPPER RIDGE AMPLIFIED INLAND OVER THE W AFRICA IS ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 75/90 NM OF LINE FROM 7N52W TO 11N40W AND DENSE CLOUD COVER WITH ISOLATED SHOWERS WITHIN 120 NM OF LINE FROM 11N40W TO OVER THE CAPE VERDE ISLANDS. STRONG ELY TRADE WINDS CONTINUE ACROSS THE TROPICAL ATLC AND WILL CONTINUE THROUGH FRI. $$ WALLACE