000 AXNT20 KNHC 260600 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 200 AM EDT Tue Jun 26 2018 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 0500 UTC. ...TROPICAL WAVES... The axis of a large amplitude tropical wave is over western Africa near 15W from 02N to 20N. Active convection is noted from 05N to 15N between 10W and 20W. This is the strongest wave to move off of Africa thus far this season, and will be strong enough to generate a surface wind shift as it propagates westward across the tropical Atlantic waters through the week. The axis of a tropical wave is near 35W from 02N to 18N, moving west around 20 kt. Scattered showers are observed within 90 nm east of the wave axis from 05N to 15N. A tropical wave is over the eastern Caribbean, with axis near 67W from 10N to 21N, moving west about 18 kt. Isolated showers are noted within 90 nm east of the wave axis from 14N to 18N. A tropical wave is moving west through the western Caribbean, with axis near 79W from 02N to 20N. Scattered showers and isolated thunderstorms are noted from 10N to 19N between 77W and 82W. This tropical wave will move into the eastern north Pacific today, where it will be monitored for possible tropical cyclone development toward the end of the week. The axis of another tropical wave is across the Yucatan peninsula near 90W. Active convection is noted over Guatemala, Honduras, and Belize. This wave will likely lose identity today as it merges into a broad low pressure over the East Pacific, with center near 08.5N97W. Conditions are favorable for this low to develop into a tropical cyclone in the EPAC within the next couple of days. ...MONSOON TROUGH/ITCZ... The monsoon trough extends southwest off the coast of western Africa at 17N17W to 16N19W to 05N31W. The ITCZ continues from 05N31W to the coast of South America near 05N51W. Except as previously described near the tropical waves, isolated moderate to occasionally strong convection is observed from 04N to 08N between 20W and 50W. ...DISCUSSION... GULF OF MEXICO... An upper-level cyclone is centered over Mexico near 23N102W. Upper diffluence east of this cyclone is supporting scattered showers and tstms over the southwest gulf waters, generally southwest of a line from 25N97W to 19N95W. The upper cyclone is forecast to continue westward through today, with its influence on convective activity over the gulf expected to diminish. An east to west surface ridge extends across the northern waters. Light to gentle winds prevail over the NE gulf, moderate to fresh over the SW gulf, and gentle to moderate elsewhere. The ridge will continue to prevail over the northern waters through the remainder of the week into the weekend. A surface trough will develop each evening over the Yucatan peninsula. The trough will shift westward into the SW Gulf each night where it will dissipate each morning. The trough will help for fresh to locally strong winds west of the Yucatan peninsula each night. CARIBBEAN SEA... See tropical wave section above for details on two waves progressing west through the Caribbean. Fresh to locally strong winds are noted across the Caribbean south of 18N between 70W and 80W, with moderate to locally fresh easterly flow over the remainder of the Caribbean waters. . The trades will diminish across the east Caribbean through tonight, but continue across the south- central Caribbean. High pressure north of the area will weaken, decreasing coverage of fresh to strong trades over the Caribbean, with these winds expected mainly over the south-central Caribbean. Nocturnal winds will pulse to fresh to strong through the next several nights in the Gulf of Honduras. ATLANTIC OCEAN... A quasi-stationary 1025 mb surface high is centered near 31N53W with a ridge extending westward to across north Florida, and a ridge extending southeast to near 23N35W. Moderate to fresh trades are noted across the tropics west of 45W with little change forecast through mid week. Strong winds are forecast for the next few days during the late afternoons through early evening hours along the north coast of Hispaniola. For additional information please visit http://www.hurricanes.gov/marine $$ AL