281 AXNT20 KNHC 011802 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 202 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 1200 UTC surface analysis and satellite imagery through 1715 UTC. ...SPECIAL FEATURES... Tropical Storm Florence centered near 14.8N 27.8W at 01/1500 UTC or 200 nm W of The Southernmost Cabo Verde Islands moving WNW at 12 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Scattered moderate to isolated strong convection is from 10N-17N between 26W-31W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT1/WTNT31 KNHC for more details. A surface trough interacting with an upper level trough is producing numerous showers and thunderstorms from Hispaniola northward across the Turks and Caicos Islands. This activity is forecast to spread west-northwestward, enhancing rainfall across Hispaniola, the Turks and Caicos Islands, the Bahamas this weekend, and across Florida and the northern Gulf of Mexico coast by early next week. Strong upper-level winds will likely prevent significant development of this system during the next couple of days, but environmental conditions are expected to become a little more favorable for a surface low pressure area to form when the disturbance moves across the Gulf of Mexico during the early to middle part of next week. There is a low chance of tropical cyclone formation over the next 48 hours. ...TROPICAL WAVES... An Atlantic tropical wave extends its axis along 54W from 02N- 14N, moving west at 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 central Caribbean tropical wave extends its axis from E Cuba near 20N75W to N Colombia near 08N77W, moving west at 10 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. Widely scattered moderate convection is over E Cuba from 19N-21N between 73W-78W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from W Africa near 15N17W to 15N22W, then resumes W of T.S. Florence near 11N30W and continues to 08N50W. See the Special Features section for convection. 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, the special feature 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 1025 mb high is centered over the W Atlantic near 34N72W. A surface trough is over the central Atlantic from 31N55W to 27N60W with scattered moderate convection within 90 nm of the trough. A 1025 mb high is over the E Atlantic near 34N42W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa