000 AXNT20 KNHC 061723 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 123 PM EDT Sat Oct 6 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 Leslie centered near 37.7N 55.8W at 06/1500 UTC or 550 nm NE of Bermuda moving E at 8 kt. Estimated minimum central pressure is 987 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. A faster motion toward the east and east- southeast is expected through the middle of next week, taking Leslie across the central and eastern Atlantic. Scattered moderate to isolated strong convection is within 75 nm of the center, and scattered moderate isolated strong convection is well NE of the center from 39N-42N between 48W-58W. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMAT3/WTNT23 KNHC,or AWIPS/WMO headers MIATCPAT3/WTNT33 KNHC, for more details. A large cyclonic gyre across the NW Caribbean is centered near the NE coast of Honduras near 17.5N86.5W. Scattered moderate to strong convection is over most of the NW Caribbean north of 14N west of 80W. Environmental conditions are expected to become gradually more conducive for further development, and a tropical depression or tropical storm is expected to form over the northwestern Caribbean Sea or the southern Gulf of Mexico on Sunday or Monday while the system moves slowly northward. Interests in the Yucatan peninsula, western Cuba, and the northern coast of the Gulf of Mexico should monitor the progress of this system during the next several days. Regardless of tropical cyclone formation, this disturbance will continue to bring torrential rains to portions of Central America, the Yucatan peninsula, and western Cuba into next week. A NW Caribbean and Gulf of Mexico gale warning has been issued with a start time of 08/0000 UTC. There is also a high chance of tropical cyclone formation within 48 hours. ...TROPICAL WAVES... A tropical wave is off the coast of W Africa along 18W from 03N- 17N, moving west at 10 kt. GOES-16 TPW imagery shows a moisture maximum surrounding the wave. The wave also has an associated 700 mb trough. Surface observations also depict the wave axis. Widely scattered moderate convection is from 03N-12N between 12W-24W. A tropical wave is along 40W from 03N-16N, moving west at 15 kt. GOES-16 TPW imagery shows a moisture maximum surrounding the wave. The wave also has an associated 700 mb trough. Widely scattered moderate convection is E of the wave axis from 08N-14N between 32W-40W. A tropical wave is along 57W from 06N-18N moving west at 10-15 kt. The wave has an associated 700 mb trough. Scattered moderate convection is E of the wave axis from 08N-12N between 46W-57W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 10N13W to 06N20W to 08N30W to 08N3W. The ITCZ extends from 08N41W to 09N56W. Aside from the convection mentioned in the tropical waves section, scattered showers are within 120 nm of the ITCZ between 41W-46W. ...DISCUSSION... GULF OF MEXICO... A 1020 mb high is centered over N Georgia near 34N83W. Surface ridging is producing 10-15 kt E to SE winds over the Gulf of Mexico. Scattered showers are noted over the NW Gulf, and over the Bay of Campeche. Elsewhere, scattered moderate convection is over W Cuba and the Yucatan Peninsula, moving N. In the upper levels, an upper level low is centered over the central Gulf near 28N91W. Expect surface ridging to prevail over the forecast area through the weekend, however, convection will advect N from the NW Caribbean to the SE Gulf for the next several days. CARIBBEAN SEA... A large cyclonic gyre is over the NW Caribbean. See above. Widely scattered moderate convection is over the northern Caribbean from 18N-22 between 60W-80W. Elsewhere, scattered moderate convection is over the central Caribbean from 15N-18N between 72W-75W. Expect active convection to persist across the central and western Caribbean during the slow drift of the cyclonic gyre into the southern Gulf of Mexico. ATLANTIC OCEAN... Three tropical waves are moving westward across the Atlantic. See above. T.S. Leslie is also described in Special Features section. A surface trough is over the E Atlantic from 31N23W to 22N33W. Scattered showers are within 180 nm east of the trough axis mainly north of 26N. Another surface trough is N of the Canary Islands from 31N10W to 29N16W. Scattered showers are within 90 nm of this trough. In the upper levels, a small upper level low is centered E of the Bahamas near 26N69W. Upper level diffluence E of the center is enhancing the convection over the Leeward Islands. A large upper level low is centered over the E Atlantic near 32N27W. Upper level diffluence E of this center is enhancing the showers over the Canary Islands. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa