000 AXNT20 KNHC 101012 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Mon May 10 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...Special Features... Caribbean Gale Warning: A recent scatterometer pass shows near gale force winds over the south-central Caribbean, particularly from 11N-14N between 72W-77W. High pressure located N of the Caribbean Sea, just E of Bermuda combined with the Colombian low will support fresh to strong winds, with frequent gusts to gale force, within about 90 nm of the coast of Colombia through early Tue morning. Then, fresh to strong trade winds will prevail over the south-central Caribbean through Fri. Seas are expected to build to 11 or 12 ft with the strongest winds tonight into early Tue morning. Please read the latest NWS High Seas Forecast issued by the National Hurricane Center, at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean through near the Sierra Leone/Guinea border at 09N13W, then continues SW to near 02N25W. The ITCZ extends from 02N25W to 03N40W to the mouth of the Amazon River near 00N50W. Scattered moderate convection is noted from the Equator to 03N between 06W-11W, from 01N-04N between 20W-25W, within 120 nm S of the ITCZ between 25W and 40W, and from 02N-05N between 42W-53W. The latter convective activity is affecting French Guiana. GULF OF MEXICO... A ridge extends across Florida into the Gulf waters. Generally gentle to moderate SE to S winds prevail over the eastern half of the Gulf while moderate to locally fresh SE to S winds are noted over the western half. A recent scatterometer pass clearly shows the wind shift associated with the trough located near the W side of the Yucatan peninsula, with fresh E-SE winds affecting the waters from 21N to 23N between 88W and 91W. Seas are generally 4 to 6 ft W of 90W based on altimeter data, and 3-4 E of 90W. Some high clouds are spreading across central Mexico into the western Gulf. Showers and thunderstorms are near the Mississippi coast and over SE Louisiana. The pressure gradient between a ridge across the Gulf region and lower pressures over Texas and NE Mexico will support moderate to locally fresh southerly winds across the W Gulf through Tue. A surface trough will develop over the Yucatan Peninsula each evening and dissipate over the SW Gulf by morning. Moderate to fresh easterly winds will be associated with this trough. A frontal boundary will linger across the northern Gulf coast through Tue night producing numerous showers and thunderstorms. Building high pressure across the SE CONUS will push the front across the Gulf on Wed, and it is expected to exit the basin by Fri night. Fresh to strong northerly winds and building seas will follow the front. CARIBBEAN SEA... A Gale Warning has been issued near the coast of Colombia for frequent gusts to gale force. Please, see the Special Features section for more details. Recent satellite derived wind data indicate fresh to strong trade winds over the south-central Caribbean, and in the Gulf of Honduras, with fresh NE-E winds in the Windward passage. Elsewhere, mainly moderate winds prevail. Seas are 8-10 ft over the south-central Caribbean, 6-8 ft in the Gulf of Honduras and 4-7 ft elsewhere, except 1-3 ft in the lee of Cuba. A diffluent pattern aloft continues to support abundant cloudiness and some shower activity over the eastern Caribbean. Plenty of moisture will persist in that region through tonight, and combine with the local effects to maintain the chance of showers over Puerto Rico and Hispaniola. ATLANTIC OCEAN... A frontal trough extends from 31N56W to 26N70W. Scattered showers are near the trough axis. A ridge, anchored on a 1026 mb high pressure located just E of Bermuda, dominates the forecast waters W of 60W. Moderate to fresh southerly winds are noted across the western periphery of the ridge and ahead of a frontal boundary located over the SE of United States. The remainder of the Atlantic is also under the influence of a ridge, with another high pressure center of 1026 mb localed near 31N44W. Farther E, another high pressure of 1023 mb is analyzed SW of the Azores and near 36N29W. Moderate to fresh trades are noted per scatterometer data across the tropical Atlantic with seas of 5-7 ft. The next cold front will move southward across the western Atlantic on Wed and stall near 31N on Thu. A low will develop along the front on Fri allowing the front to move across the waters N of 27N and W of 60W through late Sat while weakening. High pressure will follow the front. Expect building seas of 8-10 ft in northerly swell N of 30N and W of 77W Thu through Fri. $$ GR