000 AXNT20 KNHC 222354 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 754 PM EDT Fri Jun 22 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...TROPICAL WAVES... The axis of a tropical wave is near the west coast of Africa. Scattered moderate and isolated strong convection associated to this wave is noted from 04N to 10N between 15W and 20W. The axis of a tropical wave is near 34W from 03N to 20W. No significant convection is noted with this wave. The axis of a tropical wave is near 51W from 02N to 18N, moving W at 20 kt. Isolated moderate to strong convection was noted from 05N to 10N between 50W and 54W. The axis of a tropical wave is near 68W from the coast of Venezuela to the Mona passage, moving W at 10-15 knots. This wave is helping for active convection over the northeast Caribbean from 15N to 20N between 60W and 65W. The axis of a tropical wave is near 82W extending from the eastern north Pacific across Panama to westerm Cuba. The wave is helping for enhanced convection over Panama, and portions of Central America. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea near 09.5N13.5W to 05N26W. The ITCZ continues from 05N26W to 03.5N41W to the coast of Guyana near 07N58.5W. Outside of the convection associated with the tropical waves, scattered moderate convection is noted from 01N to 09N between 40W and 50W. Isolated moderate convection is noted from 06N to 10N between 55W and 61W. ...DISCUSSION... GULF OF MEXICO... A weak ridge dominates the Gulf waters, producing gentle to moderate winds with seas of 3-5 ft over the western Gulf, and seas of 3 ft or less across the eastern Gulf. Weak ridging will persist from the southeast Gulf to the coast of Texas through early next week. SE return flow will increase slightly over the western Gulf between the ridge and weak low pressure over northern Mexico starting Sat night. A surface trough will develop in the Yucatan Peninsula each afternoon, then move westward across the SW Gulf during the overnight hours, accompanied by fresh to occasionally strong east to southeast winds. CARIBBEAN SEA... A tropical wave is moving across the western Caribbean. Another tropical wave is over the eastern Caribbean. Please, see Tropical Waves section for more details. Expect increasing showers and isolated thunderstorms in association with the passage of these tropical waves. Trade winds over the south central Caribbean will strengthen and expand in areal coverage across the basin through early next week as high pressure builds across the central Atlantic. Winds could reach near gale force along the coast of Colombia by Sat night. ATLANTIC OCEAN... An upper-level trough extends from a cyclonic circulation centered near 22N69W across Hispaniola and the waters between eastern Cuba and Jamaica. The low continues to generates scattered showers and tstms mainly over the waters from 23N to 26N between 68W and 72W. High pressure of 1029 mb centered near 32N40W extends a ridge westward across the forecast area. Fresh trades are noted along the southern periphery of the ridge. This high pressure will slowly shift westward through Sat night, then remain nearly stationary near 30N55W through Tue night. The tightening pressure gradient that results over the central Atlantic will support fresh to strong trade winds and seas of 8-9 ft E of the Lesser Antilles to about 45W by early Sat morning. These marine conditions will persist on Sun with seas building up to 10 ft. Fresh to strong winds are also expected off Hispaniola at night. For additional information please visit http://www.hurricanes.gov/marine $$ AL/GR