636 AXNT20 KNHC 021721 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 121 PM EDT Sun Sep 2 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 UTC. ...SPECIAL FEATURES... ...Florence... Tropical Storm Florence is centered near 17.0N 33.2W at 02/1500 UTC or 530 nm WNW of The Southernmost Cabo Verde Islands moving WNW at 16 kt. Estimated minimum central pressure is 1000 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Scattered moderate convection is from 15N-19N between 31W-34W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT1/WTNT31 KNHC for more details. ...West Atlantic... Disorganized showers and thunderstorms over the southeastern and central Bahamas and adjacent Atlantic waters, including the Straits of Florida, are associated with a tropical wave interacting with an upper level trough. This weather system is expected to move west- northwestward across the remainder of the Bahamas, southern Florida, and the Florida Keys during the next day or so and little, if any, development is expected during that time due to strong upper level winds. However, the current unfavorable upper level wind pattern is expected to gradually change and become more conducive for a tropical depression to form over the eastern and central Gulf of Mexico by Tuesday or Wednesday. This disturbance will spread locally heavy rains across much of the Bahamas, southern Florida, and the Keys during the next day or two. There is a medium chance for tropical cyclone formation within 48 hours. ...TROPICAL WAVES... An Atlantic tropical wave extends its axis along 63W from 08N- 21N, moving west at 20 kt. This position was based on satellite imagery and model guidance. Widely scattered moderate convection is from 15N-20N between 54W-64W. A western Caribbean tropical wave extends its axis along 83W from 09N-20N, moving west at 15 kt. This wave location is based on satellite imagery, atmospheric soundings, and model guidance. Clusters of scattered moderate convection are south of E Cuba from 16N-21N between 75W-81W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from west Africa near 12N16W to 13N25W, then resumes west of T.S. Florence near 12N35W and continues to 08N45W. The ITCZ begins from that point to 09N60W. See the Special Features section for convection related to Florence. In addition, scattered moderate convection is noted along the coast of W Africa from 06N-14N between 16W-22W. Widely scattered moderate convection is from 07N-12N between 34W-42W, and from 07N-11N between 52W-57W. ...DISCUSSION... GULF OF MEXICO... An upper-level high is centered over the central Gulf of Mexico near 26N91W dominating the Gulf W of 85W. An upper level low is centered over S Florida at 26N80W. This feature is enhancing convection over the Florida Peninsula, and over the Straits of Florida. A surface trough is over the NW Gulf of Mexico from 30N92W to 28N97W. Scattered moderate to strong convection is from 25N-31N between 88W-97W. SE to S 10-15 kt return flow is over the remainder of the Gulf. Expect little change over the Gulf waters today. Expect the special feature W Atlantic trough to be a factor thereafter. CARIBBEAN SEA... An upper level low is centered south of Hispaniola near 16N72W producing upper level diffluence N of the island over the S Bahamas. More upper level diffluence is noted over the NW Caribbean S of Cuba. A tropical wave is over the western Caribbean and another is over the eastern Caribbean. See above. To the south, the eastern part of the EPAC's monsoon trough is along 10N from Costa Rica to Colombia. Scattered moderate to strong convection is 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. ATLANTIC OCEAN... Refer to the sections above for information about T.S Florence, and the Atlantic tropical wave. The upper-level low centered over S Florida is enhancing convection over the W Atlantic west of 78W. Another upper level low is centered over the central Atlantic near 27N60W. Scattered moderate convection is from 25N- 29N between 49W-56W. A surface trough extends over the W Atlantic from 26N75W to 18N76W. A 1012 mb low is embedded on the trough near 22N75W. Scattered moderate convection is from 21N-27W between 73W-78W. Clusters of widely scattered moderate convection is elsewhere W of 78W. A 1025 mb high is centered over the central Atlantic near 34N46W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa