000 AXNT20 KNHC 241757 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Thu Jun 24 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 1500 UTC surface analysis and satellite imagery through 1730 UTC. ...TROPICAL WAVES... A newly analyzed tropical wave is just off the African coast along 15W and from 15N southward, and moving W at 5 to 10 kt. A 1010 mb low pressure center is along the wave's axis near 09N15W. Scattered moderate convection is from 07N to 11N between 13W and 19W. An Atlantic tropical wave is along 34W and from 16N southward, and moving W at 10 to 15 kt. Scattered showers are noted from 01N to 06N between 30W and 40W. Another Atlantic tropical wave is along 45W from 11N southward, and moving W near 10 kt. Scattered showers prevail from 07N to 09N between 42W and 48W. A third Atlantic tropical wave is along 58W from 15N southward, and moving W at 5 to 10 kt. Scattered moderate convection is present east of the wave from 06N to 14N between 51W and 57W. A Caribbean tropical wave axis is along 76W from 10N southward, and moving W at 5 to 10 kt. Scattered moderate convection is found between eastern Cuba and Hispaniola from 18N to 19N between 72W and 80W, and also over northern Colombia. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal areas of Guinea-Bissau near 11N16W to 06N27W to 05N38W. The ITCZ continues from 05N38W to 06N45W. Scattered moderate to strong convection is found from 01N to 07N between 19W and 25W. Another monsoon trough runs westward from northern coast of Colombia through Costa Rica. Scattered showers and isolated thunderstorms are evident off the Colombian coast. GULF OF MEXICO... A surface trough runs northeastward from the Keys across southeastern Florida. Scattered showers and isolated thunderstorms are occurring across these areas from 24N to 26N between 79W to 85W. A surface ridge passes through central Florida near 27N83W, toward the central Gulf to the coast of Mexico near 20N97W. The sea heights range from 3 to 4 ft across the western Gulf, and from 1 to 3 ft elsewhere. For the forecast, high pressure will prevail across the northern waters. A diurnally induced trough will develop over the Yucatan each evening. This will lead to fresh E to SE winds pulsing each night NW of the Yucatan peninsula tonight and Fri night. Scattered showers and thunderstorms are expected to move across the eastern and central Gulf through the weekend. CARIBBEAN SEA... Refer to the Tropical Wave section above for details on convection. Moderate to fresh winds seen south of Hispaniola from 15N to 17N between 68W and 73W, and over the south central Caribbean from 11N to 15N between 73W and 77W with seas at 5 to 7 ft. Similar conditions are also present near the Windward Passage. Sea heights of 2 to 4 ft are elsewhere. The monsoon trough is along 10N/11N between 74W in Colombia, and beyond NW Costa Rica, into the eastern Pacific Ocean. Scattered showers prevail along the trough. For the forecast, the pressure gradient across the Caribbean has loosened, which is bringing moderate to fresh winds across the region. Strong winds across the south-central Caribbean is expected to begin again by early next week. A tropical wave is expected to move across the eastern Caribbean on Fri into Sat and will enhance convection throughout the region. ATLANTIC OCEAN... Refer to the Tropical Wave section above for details on convection. A surface trough from southern Florida extends northeastward to off the Georgia coast at 31N78W. Scattered showers and isolated thunderstorms are noted from central Florida northeastward to the western end of the Atlantic north of 28N. Moderate to fresh winds and seas of 6 to 8 ft are in this area. A pronounced upper- level low at 27N54W is coupling with a surface trough axis near 27N51W to trigger scattered showers and thunderstorms from 25N to 30N between 51W and 58W. Moderate to fresh winds with seas at 4 to 6 ft are found near this area. A surface ridge extends southwestward from a 1029 mb high pressure passing near Bermuda at 31N65W to central Florida near 29N82W. Fresh to locally strong N and NE winds and seas of 6 to 8 ft are within 450 nm west of the coast of Africa from 14N to 23N. Gentle winds and seas of 2 to 4 ft are present elsewhere. For the forecast, scattered showers prevail across the western Atlantic mainly west of 75W. This activity will continue through the next few days, as a frontal boundary lingers across north Florida through Fri evening. A surface trough is expected to move north of the Lesser Antilles Friday night, then continue moving westward through the weekend while staying north of Puerto Rico and Hispaniola. $$ Mora/Chan