000 AXNT20 KNHC 222353 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT THU SEP 22 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 Depression Karl was upgraded again to Tropical Storm at 22/2100 UTC. Tropical Storm Karl is centered near 26.2N 63.6W at 23/0000 UTC or about 375 nm south of Bermuda moving northwest at 14 kt. Estimated minimum central pressure is 1001 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Scattered moderate to strong convection is within 75/90 nm of a line from 25N59W to 28N65W with scattered moderate convection within 60/75 nm of a line from 28N59W to 30N63W. Please see the latest NHC Public Intermediate Advisory under AWIPS/WMO headers MIATCPAT2/ WTNT32 KNHC AND NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. Tropical Storm Lisa is centered near 120.7N 34.6W at 22/2100 UTC or about 660 nm west-northwest of the Capo Verde Islands and about 1110 nm south-southwest of the Azores moving northwest at 7 kt. Estimated minimum central pressure is 999 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Scattered moderate to isolated strong convection is from 20N-24N between 30W-34W. Please see the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT3/ WTNT23 KNHC for more details. ...TROPICAL WAVES... Tropical wave in the Caribbean extends along 87W south of 19N across Central America into the east Pacific region moving west near 20 kt over the past 24 hours. Wave is within broad 700 mb troughing over the western Caribbean. No associated deep convection is noted. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 11N15W then along 7N22W to 12N30W. Scattered moderate to isolated strong convection is within 75/90 nm along the coast of west Africa south of 12N west of 11W. ...DISCUSSION... GULF OF MEXICO... An upper ridge anchored over northeast Texas covers the west Gulf of Mexico while an upper trough extending from from an upper low over western North Carolina covers the east Gulf and is supporting a cold front that extends from the west Atlantic across Florida between Daytona Beach and Tarpon Springs. These upper features are creating a diffluent environment over the central Gulf to generate scattered to numerous showers and isolated thunderstorms from 23N-25N between 88W-95W. A weakening surface trough extends along 94W-95W south of 22N to over south Mexico. Afternoon showers and thunderstorms have developed inland over the Yucatan peninsula and over South Florida south of a cold front above. These showers and thunderstorms could move off the coast of Florida and the Yucatan later this evening. A surface ridge is building south over the north Gulf anchored by a 1021 mb high over Pennsylvania. Winds will increase slightly over the central and west Gulf Friday through Sunday as the pressure gradient tightens. An early season cold front is expected early next week off the Texas coast. CARIBBEAN SEA... An upper low is centered over the the east portion of the Dominican Republic extending an upper trough axis west to the Yucatan peninsula. This is enhancing the afternoon showers and thunderstorms that have developed inland over Puerto Rico, Hispaniola, Jamaica, and Cuba. Scattered showers and isolated thunderstorms are on the south side of the upper trough from 11N- 14N between 75W-81W and from 10N-17N between 81W-86W. The easterly winds over the Lesser Antilles is generating isolated showers and possible isolated thunderstorms from 13N-19N between 60W-64W. Tropical Storm Karl moving across the central Atlantic is disrupting the typical Atlantic surface ridge giving the Caribbean basin a weak pressure pattern. The upper trough will persist through Friday. ...HISPANIOLA... Currently scattered showers and isolated thunderstorms prevail across the island west of 69.5W. The upper low over the east portion of the Dominican Republic is generating the above activity. Showers and thunderstorms will continue through Friday when the upper trough shifts northward. Saturday will bring the return of afternoon/evening showers and thunderstorms. ATLANTIC OCEAN... The upper trough over the east Gulf of Mexico is supporting a 1012 mb low just off the coast of South Carolina near 32N79W with a cold front extending south along 30N70W then across the Florida peninsula near Daytona Beach. A surface trough is to the east extending from 32N78W along 27N78W then across extreme south Florida to along the Florida Keys. The upper trough over the Caribbean covers the far southwest Atlantic south of 23N west of 67W generating isolated showers and thunderstorms from 21N-26N between 67W-75W. Scattered showers and isolated thunderstorms are south of Tropical Storm Karl from 20N-25N between 57W-62W. A surface trough is between Tropical Storm Karl and Tropical Storm Lisa extending from 23N46W to 15N45W generating isolated showers from 15N-18N between 45W-48W. The remainder of the Atlantic north of Karl and Lisa is dominated by a surface ridge, anchored by a a 1025 mb high near 32N24W and a 1024 mb high near 33N44W. Tropical Storm Karl is expected to continue along a northwestward track through Friday before turning northeastward. Tropical Storm Lisa is expected to continue along a northwestward track through Saturday. For additional information please visit http://www.hurricanes.gov/marine $$ PAW