000 AXNT20 KNHC 021054 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 654 AM EDT Wed Sep 2 2020 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 1000 UTC. ...SPECIAL FEATURES... Tropical Storm Nana is centered near 17.0N 82.7W at 02/0900 UTC or 180 nm ENE of Limon Honduras moving W at 16 kt. Estimated minimum central pressure is 997 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Numerous moderate to scattered strong convection is evident within 120 nm in the southwest semicircle of the storm. Nana will intensify to hurricane strength off the north coast of Honduras tonight, before making landfall in Belize early Thu. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT1.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT1.shtml for more details. Tropical Storm Omar is centered near 36.2N 68.7W at 02/0900 UTC or 300 nm NW of Bermuda moving ENE at 12 kt. Estimated minimum central pressure is 1003 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Omar is experiencing significant northwest shear, and most of the convection is displaced to within 180 nm in the southeast semicircle. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT5.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT5.shtml for more details. ...TROPICAL WAVES... A tropical wave is expected to emerge off the coast of Africa later today and merge with a disturbance centered a couple of hundred miles southeast of the Cabo Verde Islands in the next day or so. Gradual development of this system is then possible. It has a low chance of development through the next 48 hours, but there is a medium chance a tropical depression could form by this weekend while it moves westward over the eastern and central tropical Atlantic Ocean. An Atlantic Ocean tropical wave is 32W/33W from 15N southward, moving W 10 to 15 knots. Scattered moderate convection is from 07N to 10N between 25W and 30W. An Atlantic Ocean tropical wave is along 45W from 15N southward, moving W 10 to 15 knots. No significant convection is observed. An Atlantic Ocean tropical wave is along 56W from 17N southward, moving W 10 to 15 knots. No significant convection is observed. A Caribbean Sea tropical wave is along 668W from 20N southward, moving W 10 to 15 knots. Scattered moderate convection is noted from 12N to 14N between 68W and 71W. A Caribbean Sea tropical wave is along 82W from 13N southward moving W 15 knots. No significant convection is evident south of Nana. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the central coastal sections of Mauritania near 19N16W to 10N25W to 13N34W to 12N47W. The intertropical convergence zone continues to 12N60W. In addition to the convection described in the tropical waves section, Scattered moderate to isolated strong convection is evident form 12N to 14N between 36W an 39W. GULF OF MEXICO... A surface ridge passes through central Florida, to a 1018 mb high pressure center that is near 28N85W. The ridge continues southwestward, to the coast of Mexico along 20N. The high pressure over the eastern Gulf will support moderate to fresh southerly winds over the western Gulf, and light to gentle breezes over the eastern Gulf through tonight. The high pressure will lift north of the area later in the week ahead of a trough entering the eastern Gulf. The trough will dissipate over the central Gulf by Fri. Looking ahead, a weak front will stall over the northern Gulf Sat and dissipate through late Sun. CARIBBEAN SEA... Please see the Special Features section above for information about T.S. Nana. A small upper level cyclonic circulation is centered off southeast Cuba near new. This not only is providing northeast shear on Nana, but is supporting a few showers between Jamaica and Haiti. It is likely also supporting the tropical wave moving into the central Caribbean, and its associated convection. Moderate to fresh E winds are noted south of Cuba, with to 5 ft seas. Gentle to moderate E winds are noted elsewhere north of 15N with light breezes south of 15N. For the forecast, high pressure building into the basin in the wake of Nana will support moderate to fresh trades over the central Caribbean through Sun with gentle to moderate breezes elsewhere. ATLANTIC OCEAN... A weak trough is moving westward through the Bahamas, south of a ridge oriented east to west along roughly 29N. Moderate to fresh E winds are noted south of 22N, with moderate SE winds off northeast Florida. Light breezes are noted in between along the ridge axis. Seas are 4 to 6 ft in open waters outside of the Bahamas. Upper level diffluence along an upper ridge axis is support a few thunderstorms from 20N to 25N between 50W and 60W. For the forecast west of 65W, the trough will move west of the area tonight into Thu, supporting fresh to locally strong winds off Hispaniola and the approaches to the Windward Passage tonight into Thu morning. The ridge will remain along 29N Thu and Fri, supporting moderate to fresh trades south of 22N. Farther east, broad ridging north of 20N is supporting moderate trade winds and 5 to 7 ft seas over most of the eastern Atlantic. $$ Christensen