000 AXNT20 KNHC 242357 AAA TWDAT Tropical Weather Discussion...update to Karl NWS National Hurricane Center Miami FL 805 PM EDT SAT SEP 24 2016 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, weather observations, radar and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...SPECIAL FEATURES... Tropical Storm Karl is centered near 33.6N 61.1W at 24/2100 UTC or about 200 nm east-northeast Bermuda and 865 nm south- southwest of Cape Race, Newfoundland moving east-northeast at 20 kt. Estimated minimum central pressure is 994 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Scattered to numerous strong convection is within 60 nm of a line from 34N60W to 37N58W with scattered moderate to isolated strong convection covering the remainder of the area from 33N-38N between 56W-62W. Please see the latest NHC Forecast/ Advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. Tropical Storm Lisa was downgraded to Tropical Depression at 24/2100 UTC. Tropical Depression Lisa is centered near 25.3N 39.7W at 24/2100 UTC or about 1000 nm southwest of the Azores and 1045 nm northwest of the Capo Verde Islands moving northwest at 10 kt. Estimated minimum central pressure is 1010 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Lisa is void of any deep convection. Please see the latest NHC Forecast/ Advisory under AWIPS/WMO headers MIATCMAT3/ WTNT23 KNHC for more details. ...TROPICAL WAVES... Tropical wave in the east Tropical Atlantic extends along 29W from 5N-14N moving west near 20 kt over the past 24 hours. Wave coincides with a broad 700 mb global model trough and is embedded within a low amplitude surge of moisture as seen on the Total Perceptible Water imagery. No associated deep convection is noted. Tropical wave in the west Tropical Atlantic extends along 56W/ 57W from 11N-21N moving west-northwest near 15 kt over the past 24 hours. Wave coincides with a broad 700 mb global model trough and is embedded within an isolated surge of moisture as seen on the Total Perceptible Water imagery. No associated deep convection is noted. Scattered showers and isolated thunderstorms are from 18N-21N between 52W-55W. Tropical wave in the south Gulf of Mexico extends along 95W south of 20N across south Mexico into the east Pacific region moving west 5 to 10 kt over the past 24 hours. Wave coincides with a 700 mb global model trough and is embedded within an area of moisture as seen on the Total Perceptible Water imagery. No associated deep convection is noted. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 14N17W then along 8N27W to 7N38W where the ITCZ begins and continues along 7N44W 11N56W to over Trinidad. Clusters of scattered moderate to isolated strong convection are from 6N-10N between 31W-39W. Clusters of scattered moderate convection are within 60 nm along the coast of west Africa from 10N-13N, from 4N-7N east of 20W to the coast of Africa, and from 10N-17N between 47W-51W. ...DISCUSSION... GULF OF MEXICO... An upper ridge extends from the Caribbean across south Mexico into the Bay of Campeche near 18N93W to over Texas near Corpus Christi. An upper low centered over south Alabama extends an upper trough southeast across the Florida peninsula into the southwest Atlantic. This is combining to give the Guff westerly flow aloft. Scattered to numerous showers and isolated thunderstorms are within 90 nm of a line from 26N90W to inland over Texas near 29N95W. A weak surface trough in the west Atlantic extends off the east coast of Florida to along the Florida Keys generating scattered showers and isolated thunderstorms inland and from 24N-26N between 80W-83W. A surface trough inland over the Yucatan peninsula is generating scattered showers and isolated thunderstorms within 60 nm along the coast of the Yucatan between 86W-92W. Isolated showers and possible isolated thunderstorms dot the area across the south/central Gulf from 22N-25N between 83W-96W. A weak surface ridge covers the Gulf anchored by a 1018 mb high off the coast of Florida near 29N85W. Weak high pressure will prevail across the northeast Gulf through the weekend. A weak cold front will reach the northwest Gulf Monday night, then stall and dissipate in the north Gulf through Tuesday night. CARIBBEAN SEA... An upper ridge is anchored in the southwest Caribbean near 13N82W and extends an upper ridge axis across Central America and south Mexico then into the Gulf of Mexico. An upper low is centered over the Mona Passage near 18N68W extending an upper trough axis southeast to the Leeward Islands. The remainder of the Caribbean is dominated by westerly flow aloft. The monsoon trough extends from over Colombia near 9N76W through a weak 1011 mb low over Panama near 9N79W to across Costa Rica near 10N84W continuing into the east Pacific region. Scattered showers and isolated thunderstorms are south of 12N between Colombia and south Nicaragua. Afternoon showers and thunderstorms have developed inland over Puerto Rico, Hispaniola, Jamaica, and Cuba again this evening. Isolated showers and thunderstorms are over the northwest Caribbean from 17N-22N west of 84W to over the Yucatan peninsula and includes the Yucatan Channel. Surface ridge over the west Atlantic will give the south/central Caribbean moderate to fresh trade winds through Wednesday. A tropical wave enter the east Caribbean Sunday. ...HISPANIOLA... Currently scattered showers and isolated thunderstorms prevail across the island again this evening. Northerly flow aloft will persist across the island providing moisture and coupled with the easterly trade winds will bring afternoon/evening showers and thunderstorms through the Tuesday. ATLANTIC OCEAN... The upper low over south Alabama extends an upper trough across the Florida peninsula near Tampa to Fort Lauderdale into the southwest Atlantic to near Andros Island in the Bahamas. A surface trough extends along the east coast of Florida from 31N81W along 27N80W to across south Florida near Fort Lauderdale generating scattered showers and isolated thunderstorms within 45 nm east of the surface trough and west of the surface trough to inland over Florida south of 29N. A second upper trough over the west Atlantic extends along 72W inducing an upper ridge between the upper troughs. This is responsible for the isolated showers and thunderstorms within 90 nm of a line from 26N79W to 23N73W. A weak 1017 mb surface high is anchored near 27N75W. A surface trough extends from southeast of Tropical Storm Karl near 31N60W along 26N63W to 23N69W with scattered showers and isolated thunderstorms within 90 nm of a line from 30N59W to 22N63W. The remainder of the Atlantic east of Karl and north of Lisa is dominated by a surface ridge anchored by a 1025 mb high near 32N29W. Tropical Storm Karl is expected to continue along a northeast track becoming a hurricane Sunday afternoon. Tropical Depression Lisa is expected to continue along a northwestward track becoming a post-tropical/remnant low later tonight. A cold front drop south into the central Atlantic Monday and Monday night becoming stationary Tuesday. For additional information please visit http://www.hurricanes.gov/marine $$ PAW