000 AXNT20 KNHC 180554 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT MON OCT 18 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...ITCZ... ITCZ AXIS IS ANALYZED ALONG 9N23W 11N35W THEN RESUMES NEAR 7N40W 6N48W 5N55W. A SURFACE TROUGH IS N OF THE ITCZ BETWEEN W AFRICA AND THE CAPE VERDE ISLANDS ALONG 19N19W TO 10N22W WITH CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 90/120 NM OF A LINE FROM 9N22W TO 24N18W. A SECOND SURFACE TROUGH IS EMBEDDED WITHIN THE ITCZ FROM 14N35W THROUGH A 1010 MB LOW NEAR 11N36W TO 7N37W WITH SCATTERED MODERATE/STRONG CONVECTION FROM 11N-14N BETWEEN 34W-37W. SCATTERED MODERATE/STRONG CONVECTION IS S OF THE ITCZ WITHIN 120 NM OF A LINE FROM 4N37W TO 8N32W WITH CLUSTERS OF SIMILAR CONVECTION FROM 4N-9N BETWEEN 35W-43W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE FROM 3N-9N BETWEEN 17W-23W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE ANCHORED IN THE CARIBBEAN COVERS THE GULF WITH SOUTHWESTERLY FLOW AND DRY AIR ALOFT...AND THUS MOSTLY CLEAR SKIES ACROSS THE GULF TONIGHT. A SHORTWAVE UPPER TROUGH IS MOVING ACROSS E TEXAS BUT IS NOT PRODUCING ANY SIGNIFICANT WEATHER AT THE MOMENT. A SURFACE ALSO COVERS THE GULF INTO THE W ATLC ANCHORED BY A 1020 MB HIGH OVER N ALABAMA. CARIBBEAN SEA... THE PRIMARY FEATURE FOR THE CARIBBEAN IS A SURFACE TROUGH THAT EXTENDS FROM 16N76W THROUGH A 1010 MB LOW CENTERED NEAR 12N78W TO INLAND OVER S NICARAGUA TO NEAR 11N85W...CONDITIONS ARE BECOMING MORE FAVORABLE FOR POSSIBLE DEVELOPMENT OVER THE NEXT DAY OR TWO BEFORE BEFORE IT INTERACTS WITH LAND. SCATTERED/ NUMEROUS STRONG CONVECTION IS N OF THE TROUGH AXIS WITHIN 30/45 NM OF LINE FROM 15N80W TO 14N82W WITH SCATTERED MODERATE/STRONG CONVECTION COVERING THE REMAINDER OF THE AREA WITHIN 180 NM NW OF THE TROUGH BETWEEN 79W-83W. BROAD UPPER RIDGE COVERS THE CARIBBEAN ANCHORED NEAR 16N76W ENHANCING THE ACTIVITY ABOVE AND CLUSTERS OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS OVER THE REMAINDER OF THE W CARIBBEAN SW OF A LINE FROM COLOMBIA NEAR 12N72W TO 20N82W INCLUDING THE PORTIONS OF CENTRAL AMERICA AND A SMALL CLUSTER OVER S HAITI AND THE GULF OF GONAVE. ALTHOUGH AN ELONGATED N/S UPPER LOW IS OVER THE LESSER ANTILLES THE AREA IS DOMINATED BY DRY AIR ALOFT AND IS NOT PRODUCING ANY SIGNIFICANT WEATHER AT THIS TIME LEAVING THE CARIBBEAN E OF 70W UNDER RATHER CLEAR SKIES TONIGHT. ATLANTIC OCEAN... BROAD UPPER TROUGH COVERS THE W INTO THE CENTRAL ATLC W OF 45W SUPPORTING A COLD FRONT THAT ENTERS THE REGION NEAR 32N47W SW ALONG 25N56W 23N66W ACROSS THE BAHAMAS NEAR 22N73W TO A WEAK 1013 MB LOW ALONG THE N COAST OF CUBA NEAR 21N77W. A PREFRONTAL SURFACE TROUGH EXTENDS FROM 26N53W ALONG 22N61W TO 21N69W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 75 NM BOTH SIDES OF THE FRONT W OF THE BAHAMA ISLANDS TO INLAND OVER CUBA WITH SCATTERED SHOWERS BETWEEN THE SURFACE TROUGH AND THE FRONTAL BOUNDARY. A SURFACE RIDGE COVERS THE W ATLC ANCHORED OVER THE ALABAMA WITH COLD AIR STRATOCUMULUS CLOUDS DOTTING THE AREA BEHIND THE FRONT. AN UPPER RIDGE JUST TO THE E OF THE UPPER TROUGH OVER THE W/CENTRAL ATLC IS GENERATING SCATTERED SHOWERS WITHIN 45/60 NM OF LINE FROM 25N50W TO BEYOND 32N41W. A SECOND UPPER TROUGH IS OVER THE E ATLC EXTENDING THROUGH 32N28W TO NEAR 20N30W BECOMING A SHEAR AXIS SW ALONG 15N37W TO 8N43W AND SUPPORTING A SURFACE TROUGH THAT EXTENDS THROUGH 32N24W ALONG 27N31W 21N39W 20N45W TO 21N49W GENERATING SCATTERED SHOWERS WITHIN 75 NM E OF THE TROUGH N OF 27N LEAVING THE REMAINDER OF THE THE E ATLC UNDER FAIR SKIES TONIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW