000 AXNT20 KNHC 101646 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Sat Jun 10 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 1200 UTC surface analysis and satellite imagery through 1620 UTC. ...SPECIAL FEATURES... Excessive Rainfall in eastern and central Cuba and the central Bahamas: The upper level trough centered over the eastern Gulf of Mexico with SW flow extending to the surface continues to maintain an Atmospheric River over Jamaica, Cuba, and the Bahamas. For the 24 hour period ending 1200 UTC this morning, 12 inches (313 mm) of rainfall was reported at Las Mercedes in Granma, Cuba. Combined with yesterday's 24 hour rainfall report of 14 inches (360 mm), Las Mercedes has observed an impressive total of 26.5 inches (673 mm) of rain over the past two days (WOW!). Additional 24 hour rainfall reports from this morning range from 8-12 inches (200-300 mm) elsewhere in Granma and Camaguey, where life- threatening flooding continues to be reported. Additional rainfall of 2-4 inches (50-100 mm) is possible over the next 24 hours in eastern Cuba and the central Bahamas. Heavy rainfall may cause flooding and mudslides, especially in the mountainous areas of eastern Cuba. Conditions are forecast to improve in Cuba by tonight, but heavy rain is expected to continue through Sun in the central Bahamas. Please refer to the latest forecast from your national meteorological service for more information. ...TROPICAL WAVES... An eastern Atlantic tropical wave is near 26W from 10N southward, moving west at 15-20 kt. This fast motion is due to strong mid-level winds. Scattered moderate convection is noted from 04N to 07N between 24W and 28W. A central Atlantic tropical wave is near 46W from 13N southward, moving west at 15 kt. No significant convection is noted at this time. A Caribbean tropical wave is near 66W from 11N southward through central Venezuela, moving west at 10 kt. No significant convection is noted at this time. The previously analyzed tropical wave in the SW Caribbean has entered the East Pacific and will no longer be described in the Atlantic Tropical Weather Discussion. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near 11N16W and continues to 06N20W to 05N29W. The ITCZ continues from 05N29W to 03N43W. Scattered showers are in the vicinity of the boundaries. GULF OF MEXICO... Light and variable winds with 1-2 ft seas prevail. For the forecast, the weak pressure gradient across the basin will maintain light to gentle winds through this evening. Low pressure will develop along a frontal boundary over Texas today which will bring moderate to locally fresh return flow over the western Gulf through Tue. By the middle of next week, the area of fresh southerly winds could expand over the western and central Gulf. CARIBBEAN SEA... Please read the Special Features section for information about Excessive Rainfall impacting Cuba. Scattered moderate convection tapping into the Atmospheric River is currently from 14N to 19N between 77W and 80W, including inland over western Jamaica. Elsewhere, moderate to locally fresh trades prevail in the eastern and central Caribbean with 4-6 ft seas. SE winds are gentle to moderate in the western Caribbean with 2-4 ft seas. For the forecast, the pressure gradient between the central Atlantic high pressure and the Colombia low will maintain fresh to locally strong winds in the south central Caribbean through Sun, with moderate to fresh winds elsewhere over the eastern and central Caribbean. Easterly trade winds will increase to fresh to strong across the south-central Caribbean by Sun night through midweek. Locally strong winds can be expected in the Gulf of Honduras by early next week. Enhanced thunderstorms will continue between eastern Cuba and Jamaica through tonight, due to the influences of an upper-level trough just NW of the area. ATLANTIC OCEAN... Please read the Special Features section for information about Excessive Rainfall for the Bahamas. Scattered moderate convection tapping into the Atmospheric River is NE of the Bahamas from 24N to 30N between 71W and 75W. A stationary front is along 31N between 70W and the US Coast; scattered showers are near this boundary. 1021 mb high pressure is centered near 26N52W, with secondary highs centered in the central Atlantic and near the Canary Islands. Light to gentle anticyclonic winds continue to prevail across the waters, increasing to moderate speeds west of 65W and on approach to the Lesser Antilles. Since such slow winds have prevailed for days, seas have subsided to 3-6 ft across the tropical Atlantic. However, Sw winds are locally fresh and seas are 6-8 ft north of 28N between 60W and 67W. For the forecast west of 55W, as the front weakens, gentle to moderate winds will prevail over the area tonight through early next week. Enhanced thunderstorms will continue over portions of the western Atlantic, including the Bahamas, through Sun. $$ Mahoney