000 AXNT20 KNHC 162337 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sun Jul 16 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 2300 UTC. ...SPECIAL FEATURES... Subtropical Depression Don is centered near 39.3N 47.0W at 16/2100 UTC or 940 nm W of the Azores moving E at 8 kt. Estimated minimum central pressure is 1010 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Convection has increased in aerial coverage in the southeastern quadrant of the cyclone, and it is also closer to the center. Don should turn southeastward on Monday, southward on Tuesday, and southwestward on Wednesday over the central Atlantic. Little change in strength is forecast during the next 72 hours, and Don could degenerate into a remnant low during that time. Please read the latest HIGH SEAS FORECAST issued by the Ocean Prediction Center, at the web-site https://www.opc.noaa.gov/text/MIAHSFAT1.shtml, and the latest Subtropical Storm Don Forecast/Advisory and the Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is along 31W, south of 17N, moving westward at 10 to 15 kt. Scattered moderate convection is noted where the wave meets the ITCZ from 11N to 14N between 31W and 35W. A tropical wave is approaching the Lesser Antilles. Its axis is along 59W, south of 20N, moving westward at 15 to 20 kt. The wave shows some inverted V pattern in the cloud field. Scattered showers are noted ahead of the wave affecting the Lesser Antilles mainly S of Guadeloupe. Moderate to fresh E to SE winds are just behind the wave axis. A tropical wave is over the central Caribbean with axis along 75W, south of 19N, moving westward at 15 to 20 kt. The wave appears to enhance convection over the northern Colombia. ...MONSOON TROUGH/ITCZ... The monsoon trough reaches the Atlantic through the coast of Senegal near 14N17W and continues to 12N28W. The ITCZ extends from 11N33W 07N52W. Scattered moderate convection is present from 09N to 13N and between 31W and 40W. GULF OF MEXICO... A weak ridge remains in control of the weather pattern across the Gulf region. Gentle to moderate E to SE winds and seas of 3 to 4 ft are noted over the SW Gulf while mainly light and variable winds and seas of 1 to 2 ft dominates the remainder of the basin. A 150 nm wide band of showers, with embedded thunderstorms extends from the NE Gulf across the N-central Gulf to about 23N94W. Numerous showers and thunderstorms are occurring over Florida. For the forecast, a ridge will persist from southwest Florida to the central Texas coast through mid week. A trough will develop over the Yucatan Peninsula each evening and move offshore. This pattern will maintain moderate to fresh winds pulsing north and west of the Yucatan peninsula during the late afternoon and evening hours. Elsewhere, gentle to moderate winds and slight seas will prevail. CARIBBEAN SEA... The most recent scatterometer data provide observations of fresh to strong winds over the south-central and SW Caribbean, including the Gulf of Venezuela. Seas are 8 to 10 ft within these winds based on altimeter data. Moderate to fresh trades and seas of 5 to 7 ft are noted in the north-central and eastern Caribbean. Moderate or weaker winds and seas of 3 to 5 ft prevail elsewhere in the basin, with the exception of 4 to 6 ft in the Windward Passage. Multilayer clouds, with possible showers, are noted over most of the central and NW Caribbean. Scattered showers and thunderstorms are flared up over Puerto Rico, Hispaniola, Jamaica and eastern Cuba. Numerous showers and thunderstorms are over the SW Caribbean. An upper level low located between Jamaica and the Cayman Islands combined with local effects supports most of this convective activity. To the south of the low, a diffluent pattern aloft is noted over the SW Caribbean. For the forecast, the pressure gradient between high pressure over the Atlantic and the Colombian low will maintain fresh to strong winds across the south central Caribbean through the period. Winds may reach near gale force along the coast of Colombia tonight. ATLANTIC OCEAN... Please refer to the SPECIAL FEATURES section for information regarding Subtropical Depression Don. The western Atlantic is dominated by a 1022 mb high pressure system located in the vicinity of Bermuda. Moderate to locally fresh winds are across the Atlantic waters of Puerto Rico and Hispaniola. Moderate S to SW winds are evident per scatterometer data N of the the NW Bahamas and E Florida along the western periphery of the ridge. Elsewhere west of 55W, moderate or weaker winds prevail. Slight to moderate seas dominate the region. Scattered showers and thunderstorms are occurring over the waters N of 25N and W of 62W. A diffluent pattern aloft is helping to induce this convective activity. The remainder of the Atlantic forecast area is under the influence of a ridge anchored on a 1028 mb high pressure located NW of the Azores near 41N34W. The pressure gradient between the ridge and lower pressure over W Africa supports fresh to strong winds between the Canary Islands and near the coast of Morocco. Similar wind speeds are also seen near the Mauritania and Western Sahara border. Seas are 8 to 10 ft within these winds. Moderate to fresh NE to E winds and seas of 6 to 9 ft dominate the Atlantic waters N of 18N and E of 40W. Moderate or weaker winds and moderate seas are prevalent in the remainder of the tropical Atlantic. For the forecast west of 55W, high pressure will prevail across the forecast waters, supporting pulses of fresh to strong NE to E winds and rough seas off Hispaniola. $$ GR