000 AXNT20 KNHC 162308 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE OCT 16 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND THE 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. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 36W/37W S OF 20N MOVING W 10 KT. THIS WAVE HAS BECOME MORE ACTIVE AS IT NOW LIES IN AN UNSTABLE ENVIRONMENT JUST E OF THE BASE OF A SHARP UPPER TROUGH. DESPITE THE INCREASE IN ACTIVITY...THE OVERALL ORGANIZATION HAS NOT IMPROVED MUCH AS IT REMAINS STRETCHED TO THE NE BY STRONG UPPER SWLY WINDS. SCATTERED MODERATE CONVECTION IS FROM 6N-14N BETWEEN 28W-41W. LOW AMPLITUDE TROPICAL WAVE IS ALONG 56W/57W S OF 14N MOVING W 10-15 KT. THIS WEAK WAVE HAS CHANGED LITTLE OVER THE PAST 24 HOURS ONLY CONSISTING OF CYCLONIC TURNING IN THE LOW-LEVEL CLOUD FIELD. NO CONVECTION IS NOTED. TROPICAL WAVE IS OVER PORTIONS OF CENTRAL AMERICA ALONG 88W S OF 20N MOVING W 10-15 KT. WIDELY SCATTERED MODERATE CONVECTION IS OVER HONDURAS AND NICARAGUA FROM 10N-16N BETWEEN 84W-89W. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 12N14W 9N20W 9N30W 7N40W 6N60W. IN ADDITION TO THE CONVECTION DUE TO THE TROPICAL WAVE... SCATTERED MODERATE CONVECTION IS FROM 3N-6N BETWEEN 27W-33W... AND FROM 4N-6N BETWEEN 41W-45W. DISCUSSION... GULF OF MEXICO... A 1005 MB LOW IS OVER THE W GULF OF MEXICO NEAR 24N94W. A SURFACE TROUGH EXTENDS NE FROM SRN LOUISIANA NEAR 30N92W TO THE LOW CENTER TO THE BAY OF CAMPECHE NEAR 20N93W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS E OF THE TROUGH AXIS OVER THE NE GULF FROM 25N-28N BETWEEN 83W-92W. SIMILAR CONVECTION IS ALSO OVER THE E BAY OF CAMPECHE FROM 18N-21N BETWEEN 89W-92W. IN THE UPPER LEVELS...AN UPPER LEVEL HIGH IS CENTERED OVER THE BAY OF CAMPECHE NEAR 22N93W. A RIDGE AXIS EXTENDS NE TO BEYOND N FLORIDA NEAR 30N81W. UPPER LEVEL MOISTURE COVERS THE E GULF E OF 93W. STRONG SUBSIDENCE IS OVER THE W GULF W OF 93W. EXPECT...CONTINUED CONVECTION OVER THE E GULF AND FLORIDA DURING THE NEXT 24 HOURS. CARIBBEAN SEA... A TROPICAL WAVE IS OVER CENTRAL AMERICA. SEE ABOVE. IN ADDITION... ELY SURFACE FLOW AND NELY UPPER LEVEL FLOW OVER CUBA PRODUCED ISOLATED MODERATE CONVECTION OVER THE HIGHER ELEVATIONS OF CUBA BETWEEN 75W-83W. MODERATE TRADEWINDS DOMINATE THE REMAINDER OF THE CARIBBEAN. IN THE UPPER LEVELS... AN UPPER LEVEL LOW IS CENTERED N OF COLOMBIA NEAR 15N78W MOVING W. UPPER LEVEL DIFFLUENCE E OF THE CENTER IS PRODUCING ISOLATED MODERATE CONVECTION OVER THE E CARIBBEAN FROM 10N-18N BETWEEN 67W-72W. EXPECT... THE TROPICAL WAVE TO PRODUCE MORE CONVECTION OVER CENTRAL AMERICA OVER THE NEXT 24 HOURS. ALSO EXPECT THE CONVECTION DUE TO THE UPPER LEVEL LOW TO MOVE W. ATLANTIC OCEAN... A SURFACE TROUGH IS OVER THE CENTRAL ATLANTIC ALONG 30N45W 27N50W 27N60W. SCATTERED SHOWERS ARE WITHIN 30 NM OF THE TROUGH. A 1020 MB HIGH IS W OF THE CANARY ISLANDS NEAR 28N22W. A SURFACE RIDGE AXIS EXTENDS W FROM THE HIGH TO 23N45W. THIS IS PRODUCING MAINLY LIGHT WINDS OVER THE SUBTROPICAL E AND CENTRAL ATLC...WHILE MODERATE TRADES PERSIST IN THE TROPICS. IN THE UPPER LEVELS...AN UPPER LEVEL RIDGE IS OVER THE W ATLANTIC N OF 20N AND W OF 70W. THE BASE OF AN UPPER LEVEL TROUGH IS OVER THE CENTRAL ATLANTIC N OF 25N BETWEEN 50W-70W. AN UPPER LEVEL HIGH IS OVER THE CENTRAL ATLANTIC CENTERED NEAR 28N40W. ANTICYCLONIC FLOW IS N OF 20N BETWEEN 30W-50W. AN UPPER LEVEL TROUGH IS OVER THE E ATLANTIC N OF 20N AND E OF 30W. A SMALL UPPER LEVEL LOW IS OVER THE TROPICAL E ATLANTIC NEAR 18N36W. FURTHER E...SWLY UPPER LEVEL FLOW IS OVER THE TROPICAL E ATLANTIC S OF 20N AND E OF 30W DUE TO THE AN UPPER LEVEL RIDGE OVER SW AFRICA. THIS FLOW IS PREVENTING TROPICAL CYCLONE FORMATION OVER THE CAPE VERDE ISLANDS. $$ FORMOSA