000 AXNT20 KNHC 222333 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT FRI JUL 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. ...TROPICAL WAVES... Tropical wave in the east Tropical Atlantic extends along 32W/33W from 9N-20N moving west near 15 kt over the past 24 hours. Wave coincides with a well defied 700 mb trough as depicted in the global models and within a highly amplified surge of moisture as seen on the SSMI Total Precipitable Water imagery. No associated deep convection. Tropical wave in the central Caribbean extends along 77W/78W from the south coast of Cuba across Jamaica to 10N moving west 10 to 15 kt over the past 24 hours. Wave is within a surge of moisture as seen on the SSMI Total Precipitable Water imagery. No associated deep convection. Tropical wave remains inland over the Yucatan this evening along 89W moving west near 10 kt over the past 24 hours. Wave coincides with a weak 700 mb trough as depicted in the global models. No associated deep convection in the Caribbean and Gulf of Mexico basins. ...ITCZ/MONSOON TROUGH... The monsoon trough extends across Africa into the east Tropical Atlantic near 21N16W and continues along 13N23W to 7N40W where the ITCZ begins and continues along 5N45W 7N53W to South America near 6N57W. Clusters of scattered moderate convection are from 10N-13N east of 28W to the coast of west Africa and from 5N-8N between 31W-42W. ...DISCUSSION... GULF OF MEXICO... A large upper ridge anchored over northwest Texas and north Alabama covers the Gulf of Mexico this evening and extends a ridge axis east into the northwest Atlantic. An inverted upper trough extends over the Gulf of Honduras to central Cuba creating a diffluent environment across the southeast Gulf to generate scattered showers and isolated thunderstorms from 24N- 28N east of 90W to over the Florida peninsula. Afternoon heating is generating scattered showers and thunderstorms inland over the Florida peninsula. A surface trough is in the southwest Gulf extending from 23N97W to Mexico near 18N94W and is generating scattered showers and isolated thunderstorms within 120/150 nm northeast of the surface trough between 19N-22N. Similar activity is over west Cuba and the Yucatan Channel. A weak surface ridge remains across the north Gulf anchored by a a 1020 mb high in the northeast Gulf near 28N83W and a 1018 mb high over the lower Mississippi Valley. The surface ridge will persist through the weekend. CARIBBEAN SEA... An inverted upper trough extends across Central America through the Gulf of Honduras to over central Cuba near 22N80W generating clusters of scattered showers and isolated thunderstorms north of 19N to over Cuba and west of 82W including the Yucatan Channel. An upper ridge is anchored near 13N76W covering the central Caribbean between 71W-80W and is providing difflunce aloft to generate scattered showers and thunderstorms from 13N- 19N between 78W-83W including the west tip of Jamaica. This activity is being enhanced by the tropical wave along 77W/78W. The last visible satellite images show an area of Saharan dust has moved over the east Caribbean east of 73W leaving skies mostly clear across Puerto Rico to the Windward Islands. 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 south-central Caribbean that will continue through the weekend. The tropical wave over the Yucatan will enter the southwest Gulf of Mexico late in the weekend. The central Caribbean tropical wave will move across the remainder of the Caribbean through Saturday night. ...HISPANIOLA... Isolated showers and thunderstorms are over the central portion of the island this evening due to daytime heating and orographic lifting. Afternoon/evening isolated showers and thunderstorms are possible through Saturday night. Sunday will see an increase in moisture with an increase in showers and thunderstorms Sunday evening into Monday. ATLANTIC OCEAN... The upper trough is digging southwest over the the far west Atlantic through 32N74W to south Florida supporting a frontal boundary north of the discussion area and a pair of surface troughs. The western surface trough extends from 31N73W to 27N79W and an eastern surface trough extends from 31N59W to 28N66W. Scattered to numerous showers and scattered thunderstorms cover the area within 330 nm southeast of the western surface trough south of 30N, with isolated showers and thunderstorms within 75 nm southeast and 120 nm northwest of the eastern surface trough. The inverted upper trough that extends to over central Cuba is generating scattered showers and isolated thunderstorms within 75 nm along the north coast of Cuba east of 80W. Otherwise, high pressure dominates the remainder of the Atlantic with a surface ridge extending from a 1031 mb high northeast of the Azores through 32N45W to 27N60W. The western most surface trough will weaken as it begins to drift west tonight through Sunday night. The surface ridge will begin to build westward across the west Atlantic Sunday into next week. Fresh to strong winds will pulse off the north coast of Hispaniola each evening through the weekend. For additional information please visit http://www.hurricanes.gov/marine $$ PAW