000 AXNT20 KNHC 130535 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 205 AM EDT WED JUL 13 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...SPECIAL FEATURES... Caribbean Gale Warning...A gale warning will go into effect for the south-central Caribbean along the coast of Colombia starting overnight tonight until early Wednesday morning. Please see the High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... Tropical wave in the Tropical Atlantic extends along 43W/44W from 8N-17N with a weak 1013 mb low along the wave near 11N, all moving west near 15 kt over the past 24 hours. Wave coincides with a 700 mb trough south of 15N as depicted in the global models and is embedded within a surge of moisture as seen on the SSMI Total Precipitable Water imagery. Clusters of scattered moderate convection are from 10N-13N between 42W-46W. Tropical wave in the Caribbean extends along 87W from 21N to over Central America moving west near 20 kt over the past 24 hours. Wave is embedded within a 700 mb trough depicted in the global models and is embedded within a surge of moisture as seen on the SSMI Total Precipitable Water imagery. No associated deep convection in the Caribbean basin. ...ITCZ/MONSOON TROUGH... The monsoon trough extends across Africa into the east Tropical Atlantic near 14N17W and continues along 10N22W to 9N28W where the ITCZ begins and continues along 8N35W to east of the tropical wave near 9N42W, then resumes west of the wave near 10N46W to the coast of South America near 8N55W. Clusters of isolated moderate convection are within 90/120 nm of a line from 7N21W to inland over Africa near 10N14W, and from 6N-12N between 46W-53W. ...DISCUSSION... GULF OF MEXICO... A cutoff upper low dominates the north Gulf centered near 26N88W generating scattered showers and isolated thunderstorms from 25N- 30N east of 89W. An upper ridge in the northwest Caribbean coupled with the tropical wave along 87W is enhancing scattered showers and isolated thunderstorms south of 24N between 83W-89W. A second upper ridge over the Florida peninsula is enhancing scattered showers and thunderstorms in the Straits of Florida from Cuba to over the Florida Keys east of 83W. A surface ridge extends from the west Atlantic across north Florida where a 1020 mb high is located near 30N83W then along the north Gulf coast to the northeast Texas. The surface ridge will persist through Friday. The diurnal surface trough will form each evening over the Yucatan and dissipate over the southwest Gulf late each morning stating again Wednesday night. CARIBBEAN SEA... An upper ridge is anchored over Honduras near 15N85W extending a ridge axis northwest to over the Yucatan peninsula. An upper trough extends from the west-central Atlantic across Hispaniola to the north coast of Colombia covering the remainder of the Caribbean. Afternoon showers and thunderstorms that developed inland over Haiti and east Cuba have moved into the Caribbean waters with scattered showers and isolated thunderstorms within 90 nm along the south coast of Cuba between 78W-81W and from 17N- 19N between 71W-75W, including the southwest portion of Haiti. The monsoon trough extends from Colombia across Panama and Costa Rica generating scattered showers and thunderstorms within 45 nm of a line from 9.5N78W to over Nicaragua near 12N84W. Saharan dust and dry air are seen on the last visible satellite imagery, leaving the Caribbean east of 80W under clear skies again tonight. The tight pressure gradient between the west Atlantic surface ridge and the lower pressure over South America is producing fresh to strong trade winds across the central Caribbean. Winds will increase to near gale force with frequently gusts to gale force along the northwest coast of Colombia during the overnight hours tonight, then to near gale force Wednesday night. The Caribbean tropical wave will move across the Yucatan tonight. ...HISPANIOLA... Scattered showers and isolated thunderstorms are from 17N-19N between 71W-75W, including the southwest portion of Haiti, leaving the remainder of the island under clear skies tonight. Afternoon or evening showers and thunderstorms will be possible over the next few days. ATLANTIC OCEAN... An upper ridge over the Florida peninsula is generating scattered showers and isolated thunderstorms in the Straits of Florida from Cuba to 26N west of 78W. An upper trough extends across the central and west Atlantic into the Caribbean supporting a surface trough that extends from 28N55W to 22N62W with isolated showers within 75 nm of the surface trough. Otherwise, a broad surface ridge dominates the Atlantic again tonight with a 1028 mb high in the northeast Atlantic near 34N33W and a ridge axis extending through 30N44W to a 1021 mb high in the west Atlantic near 29N74W continuing across north Florida and along the north Gulf of Mexico coast. This surface ridge will persist through the week. For additional information please visit http://www.hurricanes.gov/marine $$ PAW