958 AXNT20 KNHC 191644 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1244 PM EDT Sun Aug 19 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 1200 UTC surface analysis and satellite imagery through 1615 UTC. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 28W/29W from 17N southward. Scattered moderate to isolated strong monsoon trough rainshowers are from 05N to 10N from 30W eastward. An Atlantic Ocean tropical wave is along 43W/45W from 20N southward. Rainshowers are possible within 300 nm on either side of the wave. One Caribbean Sea tropical wave extends from the Mona Passage to Venezuela, along 67W/68W from 19N southward. Widely scattered moderate to isolated strong rainshowers are from 12N to 16N between 63W and 67W. A second Caribbean Sea tropical wave is along 84W/85W from 21N southward, in the western Caribbean Sea. Persistent upper level cyclonic wind flow remains in the NW corner of the Caribbean Sea. Isolated moderate rainshowers cover the waters from 14N northward from 73W westward. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Senegal near 13N17W, to 10N20W, to 09N23W, and to 09N43W. The ITCZ is along 07N46W to 06N53W, near the coast of French Guiana. Widely scattered moderate to isolated strong rainshowers are from 07N to 12N between 51W and 55W. Isolated moderate rainshowers are elsewhere, mostly from 03N to 13N, from 60W eastward. ...DISCUSSION... GULF OF MEXICO... Upper level cyclonic wind flow covers the SE half of the Gulf of Mexico. An upper level cyclonic circulation center is in the Yucatan Channel. An upper level inverted trough is in central Mexico. Isolated moderate rainshowers are in the north central Gulf, between the Florida Panhandle and south central Louisiana. Isolated moderate rainshowers are along the Florida west coast from 27N85W southward and eastward into the Straits of Florida. Rainshowers are possible elsewhere south of 26N. A surface ridge is along 28N/29N at 75W in the Atlantic Ocean, crossing Florida along 28N/29N, reaching the north central Gulf waters, and beyond the middle Texas Gulf coast. A surface trough will develop along the western Yucatan Peninsula during the late afternoons, and then drift westward across the southwest Gulf waters during the overnight hours. The surface trough will be accompanied by a fresh east to southeast wind shift. The trough will dissipate along 96W during the late mornings. An east to west ridge will extend across the Gulf waters between 26N and 27N accompanied by gentle to moderate anticyclonic flow. CARIBBEAN SEA... An upper level cyclonic circulation center is in the Yucatan Channel. Upper level cyclonic wind flow covers the Caribbean Sea from 15N northward from Jamaica. Isolated moderate rainshowers cover the waters from 14N northward from 73W westward. An upper level inverted trough extends from Hispaniola into the SW corner of the Caribbean Sea. Scattered moderate to strong rainshowers are from 07N to 10N between 78W and 81W, around Panama. The monsoon trough is along 07N/08N from 74W in Colombia westward beyond at least 88W in the eastern Pacific Ocean. Strong nocturnal easterly trade winds are expected along the northwest coast of Colombia and in the Gulf of Venezuela through the middle of the week, with the strong winds expanding as far north as 15.5N on Monday night, and with the sea heights building to 10 feet. Strong east trade winds are forecast along the south coast of Hispaniola tonight. A tropical wave along 84W/85W will continue across the western Caribbean Sea today. A second tropical wave along 67W/68W will continue westward, passing through the central Caribbean Sea early this week. A third tropical wave in the central Atlantic Ocean will reach 55W on Monday night, and reach the eastern Caribbean Sea during the middle of the week. ATLANTIC OCEAN... An upper level cyclonic circulation center is just to the north of the NW Bahamas. The cyclonic center is part of the larger-scale area of cyclonic wind flow that has been in the western part of the Atlantic Ocean along the coast of Florida during the last week or so. Isolated moderate rainshowers are from Cuba northward from 76W westward. An upper level trough passes through 32N59W to 27N70W. A surface trough is along 33N49W 29N56W. A second surface trough is along 26N68W 23N70W 20N71W. Widely scattered moderate to isolated strong rainshowers are within 120 nm on either side of the line that passes through 32N51W 28N57W 26N68W 23N70W. A surface trough is along 46W/47W from 20N to 29N. Isolated moderate rainshowers cover the waters from 20N northward between 40W and 46W. A surface ridge will dominate the forecast waters during the next several days. A broad surface trough extending from 25N68W to 20N71W will continue westward, passing through the Bahamas on Monday and on Tuesday. Light to gentle winds are expected near the trough, and moderate to fresh trades are forecast south of 23N, except becoming locally strong along the north coast of Hispaniola during the late afternoon into the evening hours. For additional information please visit http://www.hurricanes.gov/marine $$ MT