000 AXNT20 KNHC 070604 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 204 AM EDT WED SEP 7 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 0545 UTC. ...TROPICAL WAVES... A tropical wave is in the E Atlantic extending from 05N to 18N with axis near 23W, moving at 10 kt within the last 18 hours. The wave is in a region of mainly favorable deep layer wind shear and abundant low level moisture as shown by CIRA LPW imagery from the surface to 850 mb. That environment along with diffluent flow aloft support scattered showers and tstms from 05N to 15N E of 25W. A tropical wave is in the central Atlantic waters extending from 10N to 20N with axis near 52W. The wave has been repositioned from former position farther to the east, based on satellite, surface observations and latest global model guidance. Unfavorable deep layer wind shear and Saharan dry air and dust hinder convection at the time. A tropical wave is in the central Caribbean extending from 10N to 22N with axis near 72W, moving W at 10 kt within the last 24 hours. Abundant moisture in the northern wave environment along with favorable deep layer wind shear support scattered showers and isolated tstms from 16N to 22N between 68W and 76W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 17N16W to 11N22W to 04N32W to 06N47W. See the tropical waves section for convection information. Otherwise, scattered moderate convection is from 02N to 08N between 30W and 49W. ...DISCUSSION... ...GULF OF MEXICO... A broad surface ridge anchored over the SE CONUS and adjacent waters extends SW across the basin and provides return gentle to moderate flow N of 22N. The exception continues to be the Bay of Campeche where a heat surface trough along 20N88W to 18N93W provides NE fresh to strong flow within 90 nm off the W Yucatan Peninsula coast. Divergent flow aloft between an upper low in the SE basin and SW flow over the far W Caribbean support scattered to isolated showers and tstms across the Florida Keys and the straits of Florida. Similar convection is on the east Bay of Campeche associated with the surface trough. Water Vapor imagery show strong dry air subsidence across the remainder basin, which favors fair weather elsewhere. No major changes to this pattern during the next two days. On Friday night through Saturday morning, a tropical wave, currently over the central Caribbean, will move into the Yucatan Peninsula with showers. ...CARIBBEAN SEA... The main concern in the basin continues to be a tropical wave that is moving slowly across the central Caribbean generating scattered showers and tstms over Hispaniola and adjacent waters. Please refer to the tropical waves section for details. The second area with active weather is the SW basin where low pressure over NW Colombia and the presence of the monsoon trough support scattered to isolated heavy showers and tstms S of 16N W of 77W and within 120 nm off the coast of Colombia. Fresh to strong NE winds are from 18N to 20N between 73W and 76W...including the Windward Passage. Fair weather and moderate trades dominate elsewhere. Expect during the next 24 hours for the tropical wave to move over central Cuba and Panama with convection. The next wave is forecast to enter the basin Thursday. ...HISPANIOLA... Scattered showers and thunderstorms are across the island and adjacent waters associated with a tropical wave. Showers and thunderstorms are expected to continue through the next 24 hours, but weakening as the wave continues moving west. Please refer to the tropical waves section for details. ...ATLANTIC OCEAN... Diffluent flow between an upper low over the SE Gulf of Mexico and a broad upper anticyclone centered NE of Hispaniola support isolated showers across the northern Bahamas and the Florida straits. Just to the E-SE of the southern Bahamas and Turks and Caicos Islands, a tropical wave moving across the central Caribbean supports scattered heavy showers and tstms S of 23N between 68W and 74W. A surface trough extends from 23N60W to 30N60W with no convection. Farther east, a dissipating stationary front extends from 30N32W to 27N44W with isolated showers within 60 nm either side of the boundary. Lastly, a 1013 mb low in the deep tropics near 13N47W supports scattered showers and tstms within 120 nm NW quadrant from the low center. The remainder of the basin is dominated by a broad but weak surface ridge. For additional information please visit http://www.hurricanes.gov/marine $$ RAMOS