000 AXNT20 KNHC 231755 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 155 PM EDT Sun Aug 23 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 1200 UTC surface analysis and satellite imagery through 1730 UTC. ...SPECIAL FEATURES... Tropical Storm Laura is centered near 19.4N 74.3W or about 50 nm S of the E tip of Cuba at 23/1800 UTC. Laura is moving WNW at 18 kt. The estimated minimum central pressure is 1004 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Recent ASCAT passes from between 23/1300 UTC to 23/1400 UTC indicate that tropical storm force winds are occurring both north of Hispaniola and south of Haiti from 17N-22N between 70.5W-74W. Numerous moderate scattered strong convection extends out 120 nm in the NE quadrant, 210 nm SE quad, 180 nm SW quad and 60 nm NW quad. Laura is forecast to move near or over Cuba tonight and Mon, and over the SE Gulf of Mexico Mon night and Tue. Laura is expected to move over the central and NW Gulf Tue night and Wed. Very heavy rain over Hispaniola and Cuba could lead to life-threatening flash flooding and mudslides through Monday. Swells generated by Laura are affecting portions of the Virgin Islands, Puerto Rico, and Hispaniola. These swells are expected to spread across Cuba, much of the Bahamas, and the Florida Keys during the next few days. Please consult products from your local weather office. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT3.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT3.shtml for more details. Hurricane Marco is centered near 25.3N 87.4W or about 245 nm SSE of the mouth of the Mississippi River at 23/1800 UTC. Marco is moving NNW at 12 kt. Estimated minimum central pressure is 992 mb. Maximum sustained wind speed is 65 kt with gusts to 80 kt. Numerous moderate scattered strong convection is seen within 120 nm of the center in the NE quadrant, 60 nm SE quad, 75 nm SW quad and 105 nm NW quad. Scattered moderate isolated strong convection is elsewhere within 210 nm of the center in the east semicircle. The center of Marco will approach SE Louisiana early Monday. Peak seas as high as 29 feet are expected near the center of Marco in the Gulf of Mexico. A Storm Surge Warning is in effect from Morgan City Louisiana to Ocean Springs Mississippi, including Lake Borgne. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT4.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT4.shtml for more details. ..TROPICAL WAVES... An eastern Atlantic tropical wave has its axis along 33W from 02N-22N, moving W at 15 kt. A rather dry and stable environment surrounds this wave. Isolated showers are near the wave axis from 16N-18N and from 05N-11N. A short-amplitude Caribbean tropical wave has its axis along 72/73W south of 14N, moving W at 15 kt. Isolated showers and tstorms are near and within 90 nm east of the wave axis. The western Caribbean tropical wave that was analyzed along 79/80W at 23/0600 UTC has dissipated and has been removed from the analysis. ...MONSOON TROUGH/ITCZ... The monsoon trough axis passes through the coastal sections of Mauritania near 20N16W to 18N21W to 11N30W to 10N42W. The ITCZ extends from 10N42W to 10N62W. The ITCZ and monsoon trough are devoid of any significant showers and tstorms at this time. GULF OF MEXICO... Hurricane Marco is currently over the central Gulf of Mexico. It is forecast to make landfall in SE Louisiana Monday afternoon. Expect winds to hurricane force and peak seas to 29 feet through Mon afternoon near the path of Marco in the Gulf of Mexico. After landfall, Marco is forecast to turn to the WNW and slow down. Therefore, tropical storm force winds should continue through Tuesday morning for the NW Gulf waters near the coast of Louisiana. Please see the Special Features section above for additional details on Hurricane Marco. Outside of Tropical Storm Marco, fresh E to SE winds cover the Florida Straits and the eastern Gulf. The SW Gulf is currently experiencing gentle wind speeds. Moderate NE winds are in the NW Gulf. Tropical Storm Laura, currently centered just west of Haiti, will move WNW near or over Cuba, then enter the southeast Gulf of Mexico Monday evening. Laura is forecast to strengthen to a hurricane Tue evening in the central Gulf near 25N89W, then turn NNW toward Louisiana or the upper Texas coast. Laura could potentially strengthen to a category 2 hurricane over the NW Gulf with winds near 85 kt and gusts to 105 kt. Landfall is forecast to occur late Wed or early Thu along the coast of Louisiana or Texas. Expect improving conditions over the NW Gulf of Mexico late Thu into early Fri. See the Special Features section above for additional information on Laura. CARIBBEAN SEA... Tropical Storm Laura will spread tropical storm force winds and heavy squalls across the waters near Hispaniola, the Windward Passage, Jamaica, Cuba and the Yucatan Channel, through Monday evening, as it moves WNW from the Windward Passage to near Cuba to the SE Gulf of Mexico. Except seas up near 8 to 10 ft over the northern Caribbean near the path of Laura. See the Special Features section above for more on Laura. Hurricane Marco is now over the central Gulf of Mexico and is no longer affecting the Caribbean basin. However, fresh S winds are still over the Yucatan Channel. Elsewhere, scattered showers and tstorms are seen in the SW Caribbean associated with the east Pacific monsoon trough. The latest ASCAT pass shows gentle winds in the SW Caribbean and moderate winds in the Gulf of Honduras. Winds should gradually decrease tonight in the eastern Caribbean as Laura progresses farther west. ATLANTIC OCEAN... Tropical Storm Laura is centered just west of Haiti and just south of the Windward Passage. The latest ASCAT pass from this morning shows that winds in excess of 25 kt associated with Laura are occurring from 17N-26N between 67W-76W. Significant convection associated with Laura is occurring south of 22N between 68W-75W. Laura is forecast to spread tropical storm force winds and squalls over the waters north of the Windward Passage and Cuba as it moves WNW through late Monday. Seas of 12-18 ft are expected on the Atlantic Ocean side of Cuba. Strong winds and dangerous seas are also likely across portions of the Bahamas. High pressure will build westward across the area in the wake of Laura. See the Special Features section above for more on Laura. Elsewhere, a 1021 mb high is over the west Atlantic near 31N71W. An upper-level disturbance is inducing scattered showers and tstorms from 20N-30N between 55W-62W. A westward moving surface trough is analyzed from 26N49W to 17N51W. Isolated showers and tstorms are near the trough from 19N-25N. $$ Hagen