674 AXNT20 KNHC 170606 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sat Aug 17 2024 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... Hurricane Ernesto is centered near 31.4N 65.2W at 17/0300 UTC or 55 nm SSW of Bermuda, and moving NNE at 11 kt. Estimated minimum central pressure is 969 mb. Maximum sustained winds are 80 kt with gusts to 100 kt. Seas are peaking at 40 to 44 ft near the center, and at 25 to 39 ft up to 85 nm away from the center. Numerous heavy showers and isolated thunderstorms are seen in a 100 nm northeast semicircle from the center. A general NE motion with a gradual decrease in forward speed is expected through Saturday, then an increase in forward speed late Sunday into early next week. This will bring Ernesto near or over Bermuda Saturday morning, and near or east of Newfoundland Monday night. Some gradual weakening is forecast over the next day or so, though some re-intensification is possible late in the weekend. Swells generated by Ernesto will persist near the Turks and Caicos Islands and Bahamas through Saturday, along the east coast of the U.S. and near Bermuda through the weekend. These swells will likely reach portions of Atlantic Canada by late Saturday. These swells will cause life-threatening surf and rip current conditions. Please consult products from your local weather office, and stay out of the water. Ernesto is expected to produce total rain accumulations of 6 to 9 inches or 150 to 225 mm in Bermuda. This rainfall will likely result in considerable life- threatening flash flooding, especially in low-lying areas on the island. Please read the latest High Seas and Offshore Waters Forecast issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and https://www.nhc.noaa.gov/marine/offshores.php for more information. For the latest Ernesto NHC Forecast/Advisory and Public Advisory, visit www.hurricanes.gov for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave is just west of the Cabo Verde Islands near 27W from 20N southward, and moving west at 10 to 15 kt. Scattered moderate convection is seen from 06N to 10N between 25W and 31W. A central Atlantic tropical wave is near 48W from 20N southward, and moving west around 15 kt. Scattered moderate convection is found from 05N to 07N between 41W and 47W. An eastern Caribbean tropical wave is near 62W from near the northern Leeward Islands southward to northeastern Venezuela. It is moving west around 10 kt. Scattered showers and isolated thunderstorms are occurring near Leeward Islands. The wave is going to move across the eastern and central Caribbean through this weekend. This will increase the chance of showers and thunderstorms, including waters near Hispaniola, Puerto Rico and the Virgin Islands. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic along the Mauritania coast just north of Nouakchott, curves southwestward to 11N40W then turns northwestward to 15N50W. Scattered moderate convection is seen south of the trough near the coast of Guinea-Bissau and Guinea. ...GULF OF MEXICO... A weak surface trough lingers from the Straits of Florida northwestward to near New Orleans. Isolated thunderstorms are found near this feature, including the Florida Keys. A modest surface ridge reaches southwestward from a 1016 mb high over southern Mississippi to south of Tampico, Mexico. Gentle to moderate NE to E winds and seas at 2 to 4 ft are present at the northeastern and east-central Gulf, and eastern Bay of Campeche. Mainly gentle ENE to SE winds and 1 to 3 ft seas prevail for the rest of the Gulf. For the forecast, the weak high pressure will persist across the Gulf through Sun, supporting gentle to moderate breezes and slight seas. Looking ahead, light northerly breezes may briefly follow a weak cold front expected to move into the northern Gulf Mon. The front will stall and dissipate through mid week. ...CARIBBEAN SEA... A modest surface ridge related to a 1028 mb Azores High is sustaining trade winds across much of the Caribbean Sea. Convergent trades are triggering widely scattered showers and isolated thunderstorms off the coast of Honduras and Nicaragua, and near southern Haiti. Refer to the Tropical Waves section for additional weather in the basin. Tighter gradient between the aforementioned surface ridge and a 1009 mb low over northern Colombia is causing fresh with locally strong easterly winds and seas of 5 to 7 ft at the south-central basin. Moderate to fresh E winds and 3 to 5 ft seas are noted at the north-central basin. Light to gentle winds with seas at 1 to 2 ft are present at the lee of Cuba, and near Costa Rica and Panama. Gentle to moderate NE to SE winds along with 2 to 4 ft seas prevail elsewhere in the Caribbean Basin, including the Gulf of Honduras. For the forecast, the surface ridge is strengthening north of the region over the western Atlantic. This pattern will support fresh to strong trade winds over the south-central basin with moderate to rough seas, and gentle to moderate winds elsewhere with slight to moderate wave heights. ...ATLANTIC OCEAN... Please see the Special Features section for more information about Hurricane Ernesto, and the Tropical Waves section for convection in the Atlantic Basin. Outside the direct influence of Ernesto, moderate to fresh with locally strong N to W to S winds with 7 to 10 ft seas in large northerly swell are evident north of 24N between 57W and 75W. Gentle to moderate NE to ENE winds and seas of 6 to 8 ft in moderate to large NE swell exist north of 20N between 75W and the Florida-Georgia coast. Gentle to moderate southerly winds and seas at 4 to 6 ft in moderate northerly swell are present north of 18N between 57W and 75W. For the central and eastern Atlantic north of 20N between 25W and 57W, gentle to moderate ENE to ESE winds and 4 to 7 ft seas dominate. Near the Canary Islands, moderate to locally fresh N to NE winds with 5 to 8 ft seas are found north of 20N between the northwest Africa coast and 25W. Near the Cabo Verde Islands, light to gentle northeasterly and monsoonal westerly winds along with 4 to 7 ft seas in mixed moderate swells are seen from 12N to 20N between the central Africa coast and 40W. To the west from 10N to 20N between 40W and the Lesser Antilles, gentle NE to ESE trades and seas of 4 to 5 ft are present. Gentle to moderate with locally fresh monsoonal SSW to W winds with 5 to 8 ft seas in mixed moderate to large swell prevail for the remainder of the Atlantic Basin. For the forecast west of 55W, Hurricane Ernesto will move to 32.6N 64.6W Sat morning, then continue to move well north of the region through the early part of the week, before weakening late Tue. Large swells generated by Ernesto will continue to spread westward to the Bahamas through Sat, and the southeast United States coast through Mon. Expect fresh SW winds off northeast Florida late Sun into Mon, ahead of a weak cold front that will move into the area early in the week, then stall and weaken through mid week. $$ Chan