000 AXNT20 KNHC 090558 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Fri Jul 9 2021 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0500 UTC. ...SPECIAL FEATURES... Tropical Storm Elsa is centered near 38.3N 75.7W at 09/0600 UTC or 40 nm SW of Lewes, Delaware moving NE at 22 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Over the eastern Mid Atlantic States into New England, 2 to 4 inches of rain with isolated totals up to 6 inches are possible through Friday, which could result in limited flash and urban flooding for the northern Mid- Atlantic States and considerable flash and urban flooding in New England. Isolated minor river flooding is also expected. On the forecast track, Elsa will pass through the eastern mid-Atlantic states tonight and move near or over the northeastern United States on Friday and Friday night. The system should move over Atlantic Canada by Friday night and Saturday. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT5.shtml, Forecast/Advisory at https://www.nhc.noaa.gov/text/MIATCMAT5.shtml, and the High Seas Forecast issued by the NWS Ocean Prediction Center at https://ocean.weather.gov/shtml/NFDHSFAT1.php for more details. For marine information within 60 nm of the coast, please see products from your local NWS Weather Forecast Office at www.weather.gov. Caribbean Sea Gale Warning: Gale force winds over the south- central Caribbean near the coast of Colombia will continue due to the pressure gradient bewteen high pressure north of the area and lower pressure over northern Colombia. Gales will pulse tonight through early Fri with seas building to 9 to 14 ft. Please read the latest High Seas Forecast issued by the National Hurricane Center at the website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave has its axis near 28W south of 11N, moving W at 10-15 kt. No convection is noted at this time. A central Atlantic tropical wave with a large amplitude has its axis near 40W south of 25N, moving quickly W at 20 kt. No convection is noted at this time. A tropical wave has its axis near the Windward Islands along 62W south of 12N, moving W at 15 to 20 kt. Scattered moderate convection is noted over E Venezuela. A Caribbean Sea tropical wave that has its axis near 81W south of 13N across eastern Panama is moving quickly W at 20 kt. Scattered moderate to isolated strong convection is within 80 nm of the coast of Panama. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coast of Africa near 12N16W to 06N31W. The ITCZ extends from 06N32W to 03N38W. Scattered moderate convection is noted near the monsoon trough from 04N to 08N between 15W and 21W. Scattered showers are along the ITCZ. GULF OF MEXICO... A surface low over SE Texas is connected to a surface trough that extends over NE Mexico. Earlier convection in the NW Gulf has collapsed. A small area of moderate convection is noted from 22N- 23N within 50 nm of the coast of Mexico. Heavy rainfall and flash flooding will be possible along the Texas Gulf coast over the next few days. See products issued by your local National Weather Service Forecast Office for additional information. A diurnal surface trough is along the W Yucatan Peninsula. No convection is noted with this trough at this time. Fresh to locally strong SE winds are noted in the NW Gulf, with seas of 5-7 ft. Gentle flow exists around a ridge axis that extends from Tampa Bay, Florida to 27N86W in the NE Gulf with seas less than 3 ft. Fresh E winds extend from the N Yucatan Peninsula to 24N between 88W and 91W. Gentle to moderate E-SE winds prevail elsewhere throughout the basin, with seas of 4-7 ft west of 87W and 3-5 ft east of 87W. For the forecast, high pressure from the Atlantic will build westward across the area through the next few days, with relatively quiet conditions expected. The Yucatan Peninsula trough will shift westward to the southwest Gulf during the mornings through the weekend followed by fresh to strong southeast winds. Broad low pressure over South Texas will support scattered showers and a few thunderstorms across the northwest Gulf overnight. CARIBBEAN SEA... Please see the Special Features above for details on the Gale Warning in effect for the south-central Caribbean near the coast of Colombia. Elsewhere in the central Caribbean, trades diminish to strong north of the warning area with 7-10 ft seas. Fresh trades prevail in the remainder of the Caribbean, with seas of 5-8 ft. A weak surface trough is analyzed in the NE Caribbean based on surface observations, though interestingly the scatterometer pass did not detect any wind shift. For the forecast, the subtropical ridge north of the area combined with the Colombian low will enhance strong to gale force winds north of Colombia through early Friday. Fresh to strong trades will continue in the south-central Caribbean and the Gulf of Honduras through Fri night. Fresh to strong winds will pulse at night in the Gulf of Honduras through early next week. ATLANTIC OCEAN... The tropical Atlantic remains under the influence of a strong subtropical high north of the area. Moderate to locally fresh trades prevail along the southern extent of the ridge, diminishing to gentle over the W Atlantic. In the far eastern Atlantic, strong NE winds are noted north of 18N east of 20W, with near-gales between the Canary Islands and in Meteo-France's Agadir zone. Seas are 8-10 ft in this area of strong winds, 4-6 ft in the W Atlantic, and 5-7 ft in the remainder of the discussion waters. For the forecast west of 65W, high pressure will build westward across the area through Sun night. East winds will pulse to fresh to strong speeds at night between the southeastern Bahamas and Hispaniola through the period. $$ Mahoney