228 AXNT20 KNHC 012353 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 752 PM EDT Sat Sep 1 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 2345 UTC. ...SPECIAL FEATURES... Tropical Storm Florence centered near 15.6N 29.0W at 01/2100 UTC or 270 nm W of The Southernmost Cabo Verde Islands moving WNW at 14 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Scattered moderate convection is noted from 10N-18N between 26W-31W. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT1/WTNT31 KNHC for more details. ...TROPICAL WAVES... An Atlantic tropical wave extends its axis along 56W from 02N- 14N, moving west at 15-20 kt. This position was based on satellite imagery and model guidance. Isolated showers are noted within 180 nm of the wave's axis. A west-central Caribbean tropical wave extends its axis from E Cuba near 20N77W to Panama near 08N78W, moving west at 10-15 kt. This wave location is based on satellite imagery, low-level TPW imagery, and model guidance. This wave is in an area where an upper level low prevails near 17N72W enhancing convection. Scattered moderate to isolated strong convection is S of central Cuba from 16N-21N between 78W-81W. Scattered moderate convection is over E Cuba from 18N-21N between 76W-81W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from W Africa near 15N17W to 15N20W, then resumes west of T.S. Florence near 12N30W and continues to 09N50W. See the Special Features section for convection related to Florence. In addition, isolated moderate convection is noted S of the monsoon trough from 03N-14N between 08W-17W, and from 05N-10N between 31W- 47W. ...DISCUSSION... GULF OF MEXICO... An upper level low is centered S of Louisiana near 28N93W. Another upper level low is centered S of Mississippi near 30N88W. Clusters of scattered moderate convection are over the N Gulf from 23N-30N between 84W-97W. Expect a third upper level low to advect from the N Bahamas to S Florida this weekend with nocturnal thunderstorms. At the surface, a 1025 mb high is centered over the W Atlantic near 34N72W. A surface ridge extend W from the high to E Texas near 30N94W. 10-15 kt SE winds are over the Gulf. Expect the surface ridge to dominate the Gulf waters through Sun. More importantly, expect the special feature trough to be over S Florida Mon, and over the Gulf of Mexico Tue, with convection and winds. CARIBBEAN SEA... An upper level low is centered south of Hispaniola near 17N72W enhancing convection over the island and adjacent waters. A tropical wave is also over the central Caribbean. See above. Scattered showers are over the Gulf of Honduras from 15N-17N between 85W-90W. To the south, the eastern part of the EPAC's monsoon trough is along 10N from Costa Rica to Colombia. Scattered moderate to isolated strong convection is noted S of 12N. Nocturnal winds will pulse to fresh to strong in the south central Caribbean during the next several nights. Gentle to moderate winds will prevail elsewhere. The tropical wave currently over Hispaniola, will move through the western Caribbean by late Sunday into early Monday with active weather. A second tropical wave will move into eastern Caribbean Sea by Sunday. ATLANTIC OCEAN... Refer to the sections above for information about T.S Florence, and the Atlantic tropical wave. An upper level low is centered north of the Bahamas near 28N79W. This feature is enhancing convection. In addition, a surface trough extends from 25N70W to 21N75W, moving WNW. Scattered moderate convection is over the W Atlantic N of 21N and W of 71W, due to both features. Both features are also moving towards S Florida and the Gulf of Mexico. A large upper level low is centered over the central Atlantic near 31N56W. Scattered moderate convection is from 25N-30N between 45W-52W. A surface trough is over the central Atlantic from 31N55W to 27N60W with scattered moderate convection within 90 nm of the trough. To the east, a 1024 mb high is over the E Atlantic near 34N44W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa/ERA