000 AXNT20 KNHC 230039 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Thu Jun 22 2023 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 1800 UTC surface analysis and satellite imagery through 2200 UTC. ...SPECIAL FEATURES... Tropical Storm Bret is centered near 13.4N 59.6W at 22/2100 UTC or 13 nm NNW of Barbados and moving west at 14 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained winds are 55 kt with gusts to 65 kt. Recent satellite imagery indicate that westerly wind shear has increased over Bret and most of the deep convection is located more than 100 miles east of the center. Seas near the center are 25 to 27 ft and expected to gradually subside over the next few days. Little change in strength is forecast tonight while Bret passes the Windward Islands. A gradual weakening trend is anticipated once Bert enters the eastern Caribbean Sea, and the system is likely to dissipate over the central Caribbean Sea by Saturday night or early Sunday. 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. Tropical Depression Four is centered near 11.5N 44.0W at 22/2100 UTC or 1035 nm E of the Lesser Antilles and moving west-northwest at 12 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained winds are 30 kt with gusts to 40 kt. Easterly shear is still present but convection has been increasing near the center. Combined seas of 10 to 11 ft near the center are expected to build to between 13 and 15 ft by Fri morning. Some strengthening is forecast during the couple days, and the depression is likely to become a tropical storm later tonight. A weakening trend is forecast after it passes well north of the northern Leeward Islands early next week. 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 is near 23W from 14N southward, and moving westward around 10 kt. Scattered moderate convection is noted from 04N to 10N between 17W and 27W. A Caribbean tropical wave is near 75W from just south of the Windward Passage southward into northern Colombia, and moving westward at 15 kt. Scattered showers and thunderstorms are occurring over Hispaniola and northern Colombia. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic near the Guinea Bissau-Guinea border through 07N23W to 09N31W. Scattered moderate convection is observed south of the trough from 05N to 09N between the Sierra Leone/Liberia coast and 17W. The eastern end of the East Pacific monsoon trough is generating scattered showers and thunderstorms over the Caribbean waters near Panama, Costa Rica and Nicaragua. ...GULF OF MEXICO... A modest stationary front near New Orleans and across the Florida Panhandle is interacting with an mid to upper-level trough to trigger scattered showers and thunderstorms over the north-central and northeastern Gulf. A diurnal surface trough is causing widely scattered showers and isolated thunderstorms near the Yucatan Peninsula. Otherwise, a broad surface extending from southern Florida to near Tampico, Mexico continues to dominate the region. Fresh to strong ENE to ESE winds and seas of 3 to 5 ft are present at the south-central Gulf. Moderate to locally fresh southerly winds and 3 to 4 ft seas exist at the northeastern and west-central Gulf. Mainly gentle winds and seas at 2 to 3 ft prevail for the rest of the Gulf. For the forecast, the surface ridge will move little through early next week. Fresh winds will pulse north of the Yucatan Peninsula each night through Fri night as a trough develops each evening and moves offshore. A nearly stationary front along the northeastern Gulf coast will continue to bring scattered thunderstorms to those waters through Fri. Smoke from agricultural fires in Mexico is producing some hazy conditions over sections of the western Gulf S of 25N. ...CARIBBEAN SEA... Please read the SPECIAL FEATURES section for details on Tropical Storm Bret near Barbados. A surface ridge extends southwestward from near Bermuda to beyond southern Florida. Convergent southerly winds near the ridge axis are coupling with divergent flow aloft to produce scattered showers and isolated thunderstorms over the northwestern basin, including the Yucatan Channel. Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for additional convection in the basin. Tight gradient between the ridge and lower pressure over northern Colombia is causing fresh to strong easterly winds with 6 to 8 ft seas at the central basin. Fresh to strong ESE winds and seas at 5 to 7 ft are observed at the Gulf of Honduras. Outside the influence of Tropical Storm Bert near Barbados, moderate to fresh ENE winds and 4 to 6 ft seas are present at the eastern basin, and west-central basin. Light to gentle monsoonal winds with 3 to 5 ft seas in easterly swell are found at the southwestern basin. Gentle to moderate easterly winds and seas of 2 to 4 ft prevail elsewhere of the basin. For the forecast, Tropical Storm Bret will gradually weaken as it moves to near 13.5N 62.0W late tonight,then to near 13.7N 65.3W Fri afternoon with maximum sustained winds 45 kt gusts 55 kt. It will reach near 13.9N 68.8W late Fri night, then near 13.9N 72.4W Sat afternoon with maximum sustained winds 35 kt gusts 45 kt. Afterward, Bert is expected to weaken to a tropical depression near 13.8N 75.7W late Sat night and dissipate by early Sun afternoon. Farther east, Tropical Depression Four will strengthen to a tropical storm near 12.0N 45.8W late tonight with maximum sustained winds 35 kt gusts 45 kt. A slow strengthen trend will continue will it moves to near 13.2N 48.3W Fri afternoon, to near 14.4N 50.9W late Fri night, then to near 16.0N 53.5W Sat afternoon with maximum sustained winds 50 kt gusts 60 kt. It should reach near 17.6N 56.2W late Sat night, then begin to weaken as it nears 19.1N 58.8W Sun afternoon. Tropical cyclone Four is forecast to remain well east of the northern Leeward Islands through early next week. ...ATLANTIC OCEAN... Please read the SPECIAL FEATURES section for details on Tropical Storm Bret and Tropical Depression Four. Convergent southerly winds are taking advantage of divergent flow aloft to produce scattered showers and isolated thunderstorms near the Florida east coast. A cold front curves westward from the Azores across 31N40W and 29N50w to beyond 31N60W. Refer to the Monsoon trough/ITCZ and Tropical Waves sections at the beginning for additional convection in the Atlantic Basin. Moderate to fresh southerly winds and 4 to 6 ft seas are evident off the northeastern Florida north of 29N between 78W and the Georgia-northern Florida coast. Moderate to fresh ENE trades and seas of 4 to 6 ft north of 19N between 55W and the southeast Bahamas. The large dome of 1019 mb Mid-Atlantic High near 26N40W is supporting light to gentle with locally moderate winds and 2 to 4 ft seas north of 22N between 27W and 78W. Near the Canary Islands, moderate to fresh NNE trades and seas of 4 to 6 ft are noted north of 18N between the Africa coast and 27W. At the tropical Atlantic outside the influence of Tropical Storm Bert and Tropical Depression Four, moderate to fresh NNE to ESE winds and seas at 5 to 8 ft seas are present from 06N to 19N/22N between the central Africa coast and the Lesser Antilles. Light to gentle southerly and monsoonal winds with 4 to 6 ft seas in southerly swell prevail the remainder of the Atlantic Basin. For the forecast for waters west of 55W, Tropical Depression Four will strengthen to a tropical storm near 12.0N 45.8W late tonight with maximum sustained winds 35 kt gusts 45 kt, and continue to slowly strengthen as it moves to near 13.2N 48.3W Fri afternoon. It should reach near 14.4N 50.9W late Fri night, then near 16.0N 53.5W Sat afternoon with maximum sustained winds 50 kt gusts 60 kt. Afterward, it will move to near 17.6N 56.2W late Sat night, then begin to weaken as it nears 19.1N 58.8W Sun afternoon. Tropical Storm Four is forecast to remain well east of the northern Leeward Islands through early next week. Otherwise, high pressure extending from the north- central Atlantic to the central Bahamas will lift northward through early Sun ahead of tropical cyclone Four. $$ Forecaster Chan