000 AXNT20 KNHC 130005 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT Fri Oct 12 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 2315 UTC. ...SPECIAL FEATURES... Hurricane Leslie is centered near 34.4N 22.4W at 13/0000 UTC or 690 nm WSW of Lisbon, Portugal, or about 280 nm WNW of Madeira Island moving ENE at 30 kt. Estimated minimum central pressure is 972 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. A Tropical Storm Warning is in effect for Madeira Island. A fast motion toward the east-northeast is expected to continue through Saturday, followed by a slower east-northeastward motion Saturday night and Sunday. On the forecast track, the center of Leslie will pass north of Madeira Island tonight and early Saturday, approach the southwestern portion of the Iberian Peninsula on Saturday, and move inland over portions of the Iberian Peninsula late Saturday and Sunday. Leslie is expected to transition into a hurricane-force post-tropical cyclone on Saturday. Weakening is forecast after Leslie moves inland over the Iberian Peninsula, and the post-tropical cyclone is expected to dissipate by Monday. Numerous moderate to isolated strong convection extends outward to 180 nm from the center, mainly in the eastern semicircle. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT3/WTNT33 KNHC for more details. Interests in Portugal and Spain should monitor the progress of Leslie. Additional information on this system can be found in products from the Portuguese Institute for Sea and Atmosphere at www.ipma.pt. Interests in Spain should refer to products from the State Meteorological Agency at www.aemet.es. Tropical Storm Nadine centered near 16.4N 37.7W at 12/2100 UTC or 775 nm W of the Southernmost Cabo Verde Islands moving WNW at 13 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Nadine is expected to weaken to a remnant low by Saturday. A motion toward the west at a similar forward speed is expected tonight through dissipation. Scattered moderate convection extends outward to 180 nm north and east of the center. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT5/WTNT35 KNHC for more details. ...TROPICAL WAVES... A tropical wave is along 55W from 07N-21N based on the satellite imagery and observations, moving west around 10 kt. A slight maximum in Total Precipitable Water is noted with the wave. At this time, scattered showers are along and east of the wave axis from 10N-17N between 47W and the wave axis. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the eastern Atlantic from the coast of west African near 14N17W to 07N20W to 05N23W. The ITCZ extends from 05N23W to 04N28W to 05N32W. West of 32W, there is a break in the ITCZ. The ITCZ then resumes at 08N41W and continues to 06N53W. Aside from the convection related to Nadine and the tropical wave, scattered showers and isolated thunderstorms are noted within 330 nm north and 210 nm south of the ITCZ between 24W-32W. Scattered showers and thunderstorms are also noted from 02N-08N between 32W-35W. GULF OF MEXICO... A cold front extends across the basin from near Marco Island, Florida to 23N88W to 23N94W, then becomes stationary at 23N94W to to the coast of Mexico near 24N98W across northeastern Mexico. A trough in the western Bay of Campeche extends from 19N94W to 23N97W. Scattered showers are noted from 18N-24N between 94W-99W. Scattered showers are also noted from 18N-21N between 89W-94W. Drier air is north of the front. The front will shift SE across South Florida, the Straits of Florida, and the SE Gulf through Sat while weakening. High pressure will build in the wake of the front across the Gulf region. Another cold front will move into the NW Gulf Mon night, but will stall across the western Gulf through Tue night. Expect fresh to strong northerly winds and building seas behind the front. CARIBBEAN SEA... An upper-level low is over the W Caribbean near 17N81W with trough extending diagonally west of 75W. A surface trough extends from 18N87W to central Honduras near 15N86W. A Central American Gyre is developing in the southwest Caribbean. Another surface trough extends from 18N78W to 13N79W. To the south, the monsoon trough extends along 12N between 73W-84W. Scattered moderate to isolated strong convection is noted over eastern portions of Costa Rica and Nicaragua. Scattered moderate convection is in the southwest Caribbean south of 14N between 75W-84W. Scattered showers and thunderstorms are also noted near and just south of Jamaica. To the east, a diffluent flow aloft prevails over the northeast Caribbean enhancing convection across the waters between Puerto Rico and the northern coast of South America between 62W-73W. Expect moderate trade winds to prevail across the eastern Caribbean Sea through tonight. Mainly moderate to fresh trades will prevail across the basin for the start of next week. The remnants of Nadine, likely as a surface trough, are expected to reach the Lesser Antilles early next week. ATLANTIC OCEAN... Refer to the sections above for information on Hurricane Leslie, Tropical Storm Nadine, and the tropical wave along 55W. Michael has transitioned into an extratropical cyclone well to the north of the forecast area. A cold front extends across the west Atlantic from 32N72W to near West Palm Beach, Florida. Scattered showers prevail south and east of the front to about 300 nm ahead of the front, mostly to the northeast of the northwest Bahamas. A weak surface trough with minimal shower activity extends from 25N58W to 21N60W. To the east, a 1019 mb high is centered near 31N48W. For additional information please visit http://www.hurricanes.gov/marine $$ Hagen