727 AXNT20 KNHC 151731 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 131 PM EDT Wed Aug 15 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 1715 UTC. ...SPECIAL FEATURE... Subtropical Storm Ernesto is centered near 38.1N 46.0W at 15/1500 UTC or 600 nm SE of Cape Race Newfoundland, moving N at 7 kt. Estimated minimum central pressure is 1008 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT5/WTNT35 KNHC for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is just off the coast of W Africa along 19W, from 05N-16N, moving W at 15 kt. Rainshowers are possible within 300 nm on either side of the wave. An Atlantic Ocean tropical wave is along 38W, from 06N-19N, moving W at 15 kt. Rainshowers are possible within 300 nm on either side of the wave. An Atlantic Ocean tropical wave is along 56W, from 06N-22N, moving W at 15 kt. Scattered showers are from 15N-18N between 50W- 60W. A Caribbean Sea tropical wave is along 83W, from 08N-22N, moving W at 15 kt. This wave is repositioned along a 700 mb axis. This is now the only wave located in the Caribbean Sea. Scattered moderate convection is S of W Cuba from 19N- 22N between 80W-84W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of W Africa from near 09N13W, to 07N21W. The ITCZ extends from 07N21W to 10N36W. The ITCZ continues W of a tropical wave from 10N40W to 08N55W. Besides the showers mentioned in the tropical wave section, scattered moderate to isolated strong convection is from 05N-12N between 40W-47W. ...DISCUSSION... GULF OF MEXICO... NE upper level winds are over the Gulf of Mexico due to a large upper level high centered over N Mexico near 29N106W. At the surface, a 1023 mb high is centered over the W Atlantic near 30N68W. Surface ridging extends from the high to the NE Gulf of Mexico. Widely scattered moderate convection is over the E Gulf from 24N-30N between 83W-90W. Elsewhere, widely scattered moderate convection is over the Bay of Campeche from 19N-23N between 96W-98W. The surface ridge, extending westward from the Atlantic Ocean into the northern Gulf of Mexico will prevail across the region for the rest of the week. A nocturnal surface trough will move off the Yucatan Peninsula into the SW Gulf of Mexico each night, accompanied by a surge of fresh NE to E winds. CARIBBEAN SEA... A tropical waves is over the W Caribbean Sea. See above. A small upper level low is centered over the N Bahamas near 25N78W producing scattered showers. Another upper level low is centered over the Gulf of Honduras near 18N86W. Upper level diffluence from this low is enhancing the convection S of W Cuba. The monsoon trough is along 09N from Costa Rica to N Colombia. Scattered moderate to isolated strong convection is over the SW Caribbean S of 13N between 70W-80W. A surface ridge across the western Atlantic Ocean will maintain fresh trade winds in the south central Caribbean Sea for the rest of the week. Moderate to fresh trade winds are expected elsewhere. ATLANTIC OCEAN... An upper level trough is off the coast of N Florida. Scattered showers are over the W Atlantic N of 28N and W of 75W. A large upper level high is centered over the W Atlantic near 32N56W. Upper level diffluence E of this center is enhancing convection near 30N47W. At the surface, a 1023 mb high is centered over the W Atlantic near 30N68W. A surface trough is over the W Atlantic from 32N55W to 26N58W. Scattered moderate convection is from 26N-30N between 56W-61W. The tail end of another surface trough extends from 32N46W to 27N52W. Scattered moderate convection is from 29N-32N between 45W-49W. A large 1028 mb high is centered over the E Atlantic near 38N28W with ridging N of 23N between 15W-45W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa