000 AXNT20 KNHC 271028 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 628 AM EDT Wed Sep 27 2017 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 0600 UTC surface analysis and satellite imagery through 1015 UTC. ...SPECIAL FEATURES... Tropical Storm Maria is centered near 35.1N 72.9W at 27/0900 UTC or about 126 nm east of Cape Hatteras North Carolina, moving north at 4 kt. Minimum central pressure is 976 mb. Maximum sustained winds are 60 kt with gusts to 75 kt. Maria is a very large cyclone with tropical storm-force winds extending outward up to 200 nm from the center. Scattered moderate convection is within 300 nm of the storm in the eastern semicircle. Stable air on the western semicircle is resulting in mainly showers within 300 nm west of the center. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT5/WTNT25 KNHC for more details. Hurricane Lee is centered near 30.2N 56.3W at 27/0900 UTC or about 451 nm ESE of Bermuda. Lee is moving WNW at 8 kt. Estimated minimum central pressure is 971 mb. Maximum sustained winds are 95 kt with gusts to 115 kt. Lee is a small cyclone with numerous moderate and isolated strong convection confined to within 90 nm of the center. Lee is forecast to remain a hurricane the next couple of days as it turns toward the northeast on Thursday. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT4/WTNT24 KNHC for more details. ...TROPICAL WAVES... A tropical wave is off the coast of Africa with axis extending along 19W from 04N-16N, moving west at 15 kt. SSMI TPW imagery shows a very moist area. Surface and 700 mb trough are also present. Scattered moderate isolated strong convection is E of the wave axis from 08N-11N between 15W-18W. A tropical wave extends along 45W/47W from 06N-18N, moving west at 15 kt. This wave is well defined in 700 mb wind fields. A fairly dry and stable environment covers the northern portion of the wave. Scattered showers are south of 13N between 42W-50W. A tropical wave is in the central Caribbean along 74W, from 10N- 20N, moving west at 10-15 kt. The wave is embedded within a moist area ,and a weak 700 mb trough. Isolated moderate convection is within 90 nm of the wave axis. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the coast of Africa near 12N16W to 13N19W to 10N26W to 11N34W to 09N40W. The Intertropical Convergence Zone extends from 09N40W to 10N46W. The ITCZ resumes W of a tropical wave near 10N48W to 08N59W. Aside from convection associated with the tropical waves, scattered moderate to isolated strong convection is from 08N-14N between 52W-62W. ...DISCUSSION... GULF OF MEXICO... Slight surface ridging is over the N Gulf of Mexico, with mostly 5-15 kt E flow over the Gulf. Strongest winds are over the W Gulf W of 90W. In the upper levels, a large upper level trough is over the western half of the U.S. with axis along 113W. Upper level diffluence E of the axis is producing convection over S Texas and Mexico between 95W-105W. An upper level low is centered over the NE Gulf of Mexico near 28N83W with strong subsidence. Again upper level diffluence SE of the center is producing showers and convection over W Cuba, the Straits of Florida, and the Bahamas. Expect over the next 24 hours for an increase of showers and convection over the Yucatan Channel, Yucatan Peninsula, and the Bay of Campeche. CARIBBEAN SEA... A surface trough is over the W Caribbean from 21N88W to 15N88W. Scattered moderate to isolated strong convection is over the NW Caribbean, Cayman Islands, and Jamaica, from 15N-22N between 78W- 84W. Much of this convection is also enhanced by upper level diffluence. A tropical wave is over the central Caribbean. Elsewhere, scattered showers are over the Leeward and Windward Islands, while Puerto Rico has fair weather. Lastly, the eastern extent of the E Pacific monsoon trough is well into the SW Caribbean extending from SE Nicaragua to N Colombia. Isolated moderate convection is from 11N-16N between 75W-87W. Expect over the next 24 hours for continued showers and convection over the W Caribbean and Central America W of 75W. ...HISPANIOLA... Pesently fair weather is over Hispaniola. Upper level conditions will support additional afternoon and evening showers and thunderstorms on Wednesday. ATLANTIC OCEAN... Two tropical waves are moving across the basin. Please refer to the tropical waves section above for details. Tropical Storm Maria in the western Atlantic and Hurricane Lee in the central Atlantic are discussed in the special features section above. A plume of moisture is being pulled northeast across the Bahamas and surrounding waters by an upper low over the eastern Gulf of Mexico, and by low level southerly flow well to the south of Maria. This plume combined with upper level diffluence from the upper low supports numerous showers and scattered thunderstorms from 22N-28N, west of 71W. Elsewhere, surface ridging prevails across much of the remainder of the central and the eastern Atlantic, anchored by a 1021 mb high centered near 33N41W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa