688 AXNT20 KNHC 261805 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 205 PM EDT Sun Aug 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 1200 UTC surface analysis and satellite imagery through 1730 UTC. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 16W/17W from 20N southward. Broken to overcast multilayered clouds and isolated moderate rainshowers are elsewhere from 10N to 20N from 25W eastward. An Atlantic Ocean tropical wave is along 44W/45W from 21N southward. Rainshowers are possible within 120 nm on either side of the wave. A Caribbean Sea tropical wave is along 76W/77W from 20N southward. This wave is moving into an area of pre-existing upper level cyclonic wind flow. Rainshowers are possible within 120 nm on either side of the wave. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea- Bissau near 12N17W, to 10N22W, 10N34W, and 09N44W. No ITCZ was discernible. Precipitation: Scattered moderate to strong rainshowers are from 05N to 08N between 22W and 27W. Isolated to widely scattered moderate and isolated strong rainshowers are elsewhere within 150 nm on either side of the line from 08N13W to 07N22W to 08N30W to 12N37W. ...DISCUSSION... GULF OF MEXICO... An upper level trough extends from the coastal waters of Georgia and South Carolina, across NE Florida, to a central Gulf of Mexico cyclonic circulation center. Upper level cyclonic wind flow covers nearly the entire Gulf of Mexico, from 94W eastward. A second upper level cyclonic circulation center is at the coast of Mexico near 20N97W. Isolated moderate rainshowers span the Gulf of Mexico. A surface trough will develop during the evening hours in the Yucatan Peninsula, before pushing offshore into the SW corner of the Gulf of Mexico each night. A surge of moderate to fresh NE to E winds will accompany this trough. A surface ridge will dominate the rest of the Gulf waters, supporting a gentle to moderate wind flow. CARIBBEAN SEA... An upper level trough extends from a 21N63W Atlantic Ocean cyclonic circulation center, through the Mona Passage, to 16N72W just off the coast of Hispaniola, and eventually to 15N77W to the south of Jamaica. A surface trough extends from SE Cuba, northward across the Bahamas, to 28N73W in the Atlantic Ocean. Isolated moderate rainshowers are from 14N northward from 80W eastward. Isolated to widely scattered moderate rainshowers are on the Atlantic Ocean side of Cuba between the SE Bahamas and 80W. An upper level cyclonic circulation also is along the Atlantic Ocean coast of Cuba near 22N78W. An upper level inverted trough is along 85W/86W, in Nicaragua and Honduras. The monsoon trough is along 08N/09N from 74W in Colombia westward, beyond southern Costa Rica along 84W. Widely scattered to scattered moderate and isolated strong rainshowers are from 13N southward between 76W and 87W in Nicaragua. Isolated moderate rainshowers are from 14N northward from 79W westward. Fresh to strong winds, and building seas to 10 feet, will prevail in the south central Caribbean Sea through Wednesday. A stronger tropical wave will approach the waters E of the Lesser Antilles on Tuesday, bringing fresh easterly winds and sea heights about 8 feet. The wave will enter the E Caribbean early on Wednesday, increasing the likelihood of rainshowers in the Lesser Antilles. ATLANTIC OCEAN... The southernmost point of a surface trough is 31N81W along the coast of SE Georgia. An upper level trough extends from NE Florida to a central Gulf of Mexico cyclonic circulation center. Widely scattered moderate to isolated strong rainshowers are to the NW of the line that passes through 32N71W to 28N80W along the eastern coast of Florida. An upper level trough extends from 32N68W, to a 28N70W cyclonic circulation center, to a second cyclonic circulation center that is near 22N78W along the coast of Cuba. Isolated to widely scattered moderate rainshowers are elsewhere from 20N northward 66W and 80W. An upper level trough is at the western edge of the Canary Islands, from a 35N16W cyclonic circulation center to 24N21W. A second upper level trough extends from a 32N43W cyclonic circulation center, to 28N50W, to a second cyclonic circulation center that is near 21N63W. The trough continues toward the southern side of Hispaniola, in the Caribbean Sea. A surface trough extends from a 1022 mb low pressure center that is near 31N44W, to 29N51W. Isolated moderate rainshowers are elsewhere to the NW of the line that passes through 32N38W to 24N50W to 18N62W. A central Bahamas surface trough is forecast to move across the area through Monday. Gentle to moderate winds will be associated with this trough. The wind speeds will pulse to fresh to strong at night just N of Hispaniola through Thursday. A weak surface ridge will dominate the rest of the forecast area, supporting gentle to moderate E to SE wind flow. For additional information please visit http://www.hurricanes.gov/marine $$ MT