000 AXNT20 KNHC 120526 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 126 AM 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...SPECIAL FEATURES... Tropical Storm Michael is centered near 37.1N 76.1W at 12/0300 UTC or 10 nm NNE of Norfolk Virginia moving NE at 22 kt. Estimated minimum central pressure is 988 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. An east-northeastward motion with a significant increase in forward speed is expected during the next couple of days. On the forecast track, the center of Michael will move off the coast of Virginia within the next hour or two and then begin to race east-northeastward across the northwestern Atlantic Ocean. Michael is expected to become a post-tropical low overnight and then intensify over the western Atlantic on Friday. Gale to storm-force winds are expected over portions of southeastern Virginia, extreme northeastern North Carolina, and the Delmarva Peninsula overnight and Friday morning when Michael becomes post-tropical off the Mid-Atlantic coast. Michael is expected to produce total rain accumulations of 3 to 5 inches across southeast Virginia, southeast Maryland, Delaware, and southern New Jersey. Isolated maximum totals of 7 inches are possible. This rainfall could lead to life-threatening flash floods. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC for more details. Hurricane Leslie is centered near 30.9N 33.9W at 12/0300 UTC or 550 nm SW of the Azores moving ENE at 23 kt. Estimated minimum central pressure is 969 mb. Maximum sustained wind speed is 80 kt with gusts to 100 kt. The government of Portugal has issued a Tropical Storm Warning for Madeira Island. A continued east- northeast motion with an increase in forward speed is expected through Friday. Leslie is forecast to slow down and turn toward the east or east-southeast by Saturday. On the forecast track, Leslie will pass near Madeira Island by late Saturday. Some gradual weakening is forecast during the next 72 hours, and Leslie could transition into a post-tropical low by Sunday. Leslie is expected to produce storm total accumulations of 3 to 6 inches across Madeira Island through Sunday. This could lead to flash flooding and landslides over mountainous terrain. Scattered moderate to isolated strong convection is from 29N-37N between 30W-39W. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT3/WTNT33 KNHC for more details. Tropical Storm Nadine is centered near 14.9N 35.5W at 12/0300 UTC or 640 nm W of the Southernmost Cabo Verde Islands moving WNW at 8 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. A west-northwestward to westward motion with an increase in forward speed is expected on Friday and Saturday. Weakening is forecast during the next couple of days, and Nadine is expected to dissipate by Saturday night. Scattered moderate to isolated strong convection is from 13N-18N between 31W-36W. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT5/WTNT35 KNHC for more details. ...TROPICAL WAVES... A tropical wave is along 53W from 07N-21N based on the satellite imagery and observations. Maximum in Total Precipitable Water is noted with the wave. Scattered showers are near the wave axis particularly North of 12N. The remnants of a tropical wave is S of Jamaica. This feature is now a surface trough from 17N78W to 11N79W, nearly stationary. Scattered showers and thunderstorms are within 120 nm of the trough. A broad area of low pressure is expected to develop in the next day or two. This system is forecast to slowly move westward toward Nicaragua and Honduras through early next week. Environmental conditions are expected to support some slow development, however, interaction with land could limit the chance of formation on Monday or Tuesday. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean near 13N17W and continues westward to near 09N20W. The ITCZ extends from 09N20W to 05N30W to 09N36W to 10N51W. The ITCZ resumes west of Tropical from 10N55W to 10N61W. Other than the convection mentioned above associated with Nadine, isolated moderate convection is from 03N-09N between 18W-34W. GULF OF MEXICO... A cold front extends from N Florida near 31N83W to the central Gulf near 24N90W to 24N98W. Isolated moderate convection is along and within 240 nm S of the front. This front will continue moving southeast reaching S Florida Saturday. Scatterometer data depicts gentle to moderate winds across the basin. Elsewhere, scattered moderate to isolated strong convection is over the southern Bay of Campeche and S Mexico S of 20N. CARIBBEAN SEA... An upper-level low is over the W Caribbean near 16N83W. A Central American Gyre is developing in the southwest Caribbean enhancing convection between 73W-83W. In the same area, a surface trough has been analyzed. Refer to the Tropical Waves section above for details about this feature. To the east, a diffluent flow aloft prevails over the northeast Caribbean enhancing convection across the waters south of Hispaniola and Puerto Rico. Expect moderate tradewinds to prevail across the eastern Caribbean Sea through Friday. Moderate NE swell from Hurricane Leslie will move through the Atlantic waters and Caribbean passages through Friday. ATLANTIC OCEAN... Refer to the sections above for information on Hurricane Leslie, Tropical Storm Nadine, and the tropical wave along 51W. Scattered showers prevail across the west Atlantic west of 73W due to T.S. Michael's rainband. To the east, a 1018 mb high is centered near 32N659W. Another 1019 mb high is over the Canary Islands near 27N17W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa