000 AXNT20 KNHC 191155 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sun Mar 19 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 0600 UTC surface analysis and satellite imagery through 1030 UTC. ...SPECIAL FEATURES... Central Atlantic Significant Swell Event: Residual NW swell continues to generate 11 to 12 ft seas north of 26N between 36W and 48W. This swell should subside further as it moves eastward today, allowing seas to drop below 12 ft later this afternoon. Gulf of Mexico Gale Warning: Northerly near-gale to gale winds behind a cold front will persist offshore near Tampico and Veracruz, Mexico through this evening. In addition, frequent wind gusts to gale-force are also expected across the central Gulf and eastern Bay of Campeche until late this evening. Seas are peaking at 11 to 13 ft under the strongest winds. Once the front has moved south of the Gulf into the northwestern Caribbean and Cuba late tonight, winds across the Gulf should gradually subside through Mon. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and Offshore Waters Forecast at https://www.nch.noaa.gov/marine/offshores.php for more details on the Gale Warning and Significant Swell above. East-central Atlantic Gale Warning: A scatterometer pass earlier last night provided observations of gale force winds near the coast of Morocco in the Meteo-France offshore zones of Agadir. Seas in this area range from 9 to 12 ft. Please see the Meteo- France High Seas Forecast and Warning at website: https://www.gmdss.org/II.html for more information. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic Ocean along the coast of Liberia near Monrovia, and extends west-southwestward to 02N21W. An ITCZ continues westward from 02N21W across 02N35W to the Amazon River Delta in Brazil. Scattered moderate convection is seen near both features from the Equator to 05N between 10W and 46W. ...GULF OF MEXICO... Please see the Special Features section about an ongoing Gale Warning. A strong cold front extends southwestward from near Fort Myers, Florida to near Tabasco, Mexico. Scattered showers and isolated thunderstorms are occurring up to 50 nm along either side of the front. Strong surface convergence behind the front is triggering similar conditions over the west-central Gulf. Outside the Gale Warning areas, fresh to strong northerly winds and seas of 7 to 11 ft are present behind the front. Gentle to moderate NE to SE winds with 4 to 6 ft seas are noted at the southeastern Gulf east of the front. For the forecast, once this front has passed the Florida Straits and Yucatan Channel into the northwestern Caribbean Sea and Cuba late this evening, winds and seas across the Gulf will begin to subside. High pressure building in the wake of the front should allow winds and seas to diminish further across the eastern Gulf through Tue. Fresh to strong winds are anticipated to persist and shift SE at the western Gulf Mon night into Tue evening, then become moderate to fresh by midweek. ...CARIBBEAN SEA... A weakening shear line extends westward from the central tropical Atlantic across Martinique to the eastern Caribbean Sea near 14N68W. Patchy showers are found along and up to 140 nm north of this feature, including Puerto Rico, the Virgin and Leeward Islands. A broad surface trough is triggering scattered showers and thunderstorms near the Yucatan Channel and Gulf of Honduras, including the western tip of Cuba. Convergent southerly winds are producing isolated thunderstorms over eastern Cuba. Fresh to strong ENE to E winds and seas of 6 to 8 ft are present at the south-central, north-central and northeastern basin. Gentle to moderate southeasterly winds with 3 to 5 ft seas are noted at the northwestern basin, including the Yucatan Channel. Moderate with locally fresh E winds and seas at 4 to 6 ft prevail for the rest of the basin. For the forecast, a large 1026 mb high pressure north of the shear line near 29N54W will support fresh to occasionally strong NE to E winds, and moderate to locally rough seas across the eastern and central Caribbean through Mon. Moderate northerly swell will persist at the Atlantic passages through midweek next week. Fresh to strong easterly winds will continue to pulse off Colombia through Mon, then increase to between strong and near- gale by Tue. These winds might reach gale-force on Tue and Wed nights. Winds and seas are expected to increase in the Yucatan Channel and far northwestern Caribbean this evening through Mon as a cold front moves into the area. These winds and seas should gradually diminish late Mon night through Tue as the stalled front dissipates. ...ATLANTIC OCEAN... Please see the Special Features section about significant northerly swell in the central Atlantic, and gales at the east- central Atlantic. A weakening cold front curves southwestward from the Azores across 31N33W to 16N53W, then continues as a shear line through Martinique in the Leeward Islands. Patchy showers are seen near and up to 80 nm southeast of the front, and near and up to 80 nm northwest of the shear line. Another cold front reaches southwestward from off the Carolinas coast across 31N76W through southern Florida. Scattered showers and thunderstorms are flaring up along and up to 50 nm northwest of this boundary. Convergent southerly winds farther south are generating scattered showers and isolated thunderstorms over the northwest and central Bahamas. Other than the significant swell, moderate to fresh N to NE winds with 8 to 10 ft seas are found near and up to 250 nm northwest of the cold front/shear line. To the northwest, a large 1026 mb high near 29N54W is sustaining light to gentle winds and seas of 4 to 6 ft from 24N to 29N between 55W and 73W. Fresh to strong southerly winds and 6 to 8 ft seas are evident east of the second cold front north of 29N between 73W and 75W. Moderate to fresh NW winds and seas at 5 to 7 ft are noted behind this front north of 27N between 75W and the Georgia-Florida coast. At the east-central Atlantic outside the gales, moderate to fresh with locally strong NNE to NE trades and seas of 7 to 9 ft exist north of 19N between the African coast and 21W. Farther west, gentle to moderate NNE trades with 6 to 7 ft seas are found north of 20N between 21W and 32W. To the south, moderate to fresh NNE to ENE trades and seas of 6 to 9 ft in moderate northerly swell dominate from 04N to 19N/20N between the central African coast and the Lesser Antilles. Light to gentle winds and 5 to 7 ft seas in gentle swell prevail for the remainder of the basin. For the forecast W of 55W, the 1026 mb high is supporting fresh to occasionally strong E to SE winds off Hispaniola through this evening. Large northerly swell west of 65W will subside to moderate by Mon, except for waters northeast of the northern Leeward Islands. The cold front east of Florida will move farther east and stall from Bermuda to the Straits of Florida by Mon morning. Looking ahead, winds and seas will increase north of the stalled front Mon through mid week with NE swell. $$ Forecaster Chan