000 AXNT20 KNHC 172357 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST TUE NOV 17 2009 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... THE ITCZ AXIS IS CENTERED ALONG 11N15W 8N20W 6N30W 8N51W 5N55W. SCATTERED MODERATE CONVECTION IS ALONG THE COAST OF WEST AFRICA FROM 6N-8N BETWEEN 10W-13W. SCATTERED MODERATE CONVECTION IS ALSO FROM 5N-7N BETWEEN 17W-20W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 9N-12N BETWEEN 40W-44W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A COLD FRONT EXTENDS FROM THE FLORIDA PANHANDLE TO THE THE BAY OF CAMPECHE ALONG 30N85W 26N86W 23N90W 18N93W. SCATTERED SHOWERS ARE WITHIN 120 NM W OF THE FRONT. A STATIONARY FRONT IS INLAND OVER MEXICO E OF THE SIERRA MADRE ORIENTAL MOUNTAINS ALONG 17N86W 20N98W 23N99W. SCATTERED SHOWERS ARE WITHIN 120 NM E OF THE FRONT TO THE GULF COAST. A 1021 MB HIGH IS CENTERED OVER SOUTH TEXAS NEAR 27N98W. A TIGHT SURFACE PRESSURE GRADIENT IS OVER THE SW GULF OF MEXICO BEHIND THE COLD FRONT PRODUCING 20-25 KT NE WINDS. IN THE UPPER LEVELS...A TROUGH IS OVER THE W GULF W OF 85W. AN UPPER LEVEL RIDGE IS OVER THE E GULF E OF 85W TO INCLUDE FLORIDA. A 240 NM SWATH OF UPPER LEVEL MOISTURE AND BROKEN TO OVERCAST HIGH CLOUDS EXTENDS FROM THE FLORIDA PANHANDLE TO THE BAY OF CAMPECHE. STRONG SUBSIDENCE COVERS THE REMAINDER OF THE GULF. EXPECT...THE COLD FRONT TO EXTEND FROM CENTRAL FLORIDA TO THE YUCATAN PENINSULA IN 24 HOURS WITH SHOWERS. CARIBBEAN SEA... MUCH OF THE CARIBBEAN IS EXPERIENCING GENERALLY FAIR WEATHER UNDER THE INFLUENCE OF DRY AIR AND SUBSIDENCE ASSOCIATED WITH AN UPPER LEVEL RIDGE COVERING THE WRN CARIBBEAN EXTENDING FROM THE YUCATAN PENINSULA AND WRN CARIBBEAN ACROSS S FLORIDA TO THE WRN ATLC. ISOLATED SHOWERS/THUNDERSTORMS ARE HOWEVER IN THE SW CARIBBEAN AFFECTING PORTIONS OF COSTA RICA/PANAMA S OF 11N BETWEEN 76W-84W DUE TO SURFACE CONVERGENCE NEAR THE E PACIFIC ITCZ. WIDELY SCATTERED MODERATE CONVECTION IS OVER THE LEEWARD ISLANDS FROM 17N-21N BETWEEN 59W-62W DUE TO A SURFACE TROUGH. AN UPPER LEVEL TROUGH ALSO EXTENDS FROM THE W ATLANTIC SWD ACROSS THE LESSER ANTILLES SUPPORTING THE SURFACE TROUGH N OF THE LEEWARD ISLANDS AND PROVIDING AN UPPER DIFFLUENT ZONE ENHANCING CONVECTION. MODERATE TO FRESH TRADE WINDS ARE ACROSS MUCH OF THE BASIN. EXPECT... SHOWERS/THUNDERSTORMS TO CONTINUE OVER THE FAR NE CARIBBEAN FOR THE NEXT 24 HOURS AS THE SURFACE TROUGH REMAINS MAINLY STATIONARY. ALSO EXPECT MORE SHOWERS/THUNDERSTORMS OVER THE SW CARIBBEAN OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... A 1009 MB DEEP LAYERED LOW IS OVER THE W ATLANTIC CENTERED NEAR 28N65W. A SURFACE TROUGH EXTENDS S FROM THE LOW TO N OF HISPANIOLA NEAT 20N70W. A SECOND SURFACE TROUGH EXTENDS TO THE E ALONG 28N60W 21N62W. WIDELY SCATTERED MODERATE CONVECTION EXTENDS 240 NM E OF THIS TROUGH. THIS CONVECTIVE ACTIVITY IS ALSO ENHANCED BY DIFFLUENT FLOW ALOFT FROM AN UPPER LEVEL LOW CENTERED NEAR 27N63W. A 1025 MB HIGH IS CENTERED OVER THE E ATLANTIC NEAR 32N31W. A RIDGE AXIS EXTENDS SW FROM THE HIGH TO 20N55W. A DISSIPATING COLD FRONT IS JUST INLAND OVER WEST AFRICA FROM 31N9W TO 21N16W. SCATTERED SHOWERS ARE FROM 32N-34N BETWEEN 10W-12W. $$ FORMOSA