000 AXNT20 KNHC 201758 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Thu Apr 20 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 1700 UTC. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic through the coast of Guinea- Bissau just south of Bissau then southwestward to 04N21W. An ITCZ extends westward from 04N21W across 03N30W to 04N40W. Numerous moderate to scattered strong convection is occurring near both features from 01N to 07N between 10W and 23W. Scattered moderate to isolated strong convection is observed farther west near the ITCZ south of 06N between 23W and 40W. ...GULF OF MEXICO... A surface ridge stretches west-southwestward from a 1025 mb high over southern Georgia to just north of Tampico, Mexico. Convergent easterly winds are causing scattered showers and isolated thunderstorms at the southeastern Gulf, including the Florida Straits and northwestern coast of Cuba. Moderate with locally fresh E to SSE winds and 3 to 5 ft seas are found across the entire Gulf. For the forecast, the subtropical ridge positioned between the southeastern United States and Bermuda, and lower pressures over Mexico will continue to enforce moderate to fresh SE to S return flow over the Gulf of Mexico through Fri. The diurnal trough forming over the Yucatan will promote strong E winds over eastern Bay of Campeche tonight. Agricultural and seasonal fires over Mexico and Central America result in smoke and haze over the the southwestern Gulf and the Bay of Campeche. Mariners may experience reduced visibility in these waters. Winds will diminish across the Gulf on Fri. A cold front that is expected to enter the northwestern Gulf Fri night. Moderate to fresh N to NE winds will prevail behind the front on Sat. By Sun morning, the dissipating front will extend from southwest Florida to near the Texas-Mexico border. Looking ahead, as a surface ridge builds to the north of the Gulf, fresh to strong E to SE winds are expected on Sun and Mon over most of the western and central Gulf. ...CARIBBEAN SEA... A 1022 mb Mid-Atlantic High near 28N49W sustains a relatively fair trade-wind regime for much of the basin. The southern end of a surface trough is triggering scattered showers and isolated thunderstorms over eastern Cuba and northeast of Jamaica. Fresh with locally strong NE to E winds and seas of 6 to 8 ft are present at the south-central basin, north of Colombia. Gentle to moderate ESE winds and seas at 2 to 4 ft are noted at the northwestern basin. Moderate easterly winds with 4 to 6 ft seas prevail for the rest of the basin. For the forecast, the Mid-Atlantic High will weaken over the next couple of days. This will allow the fresh to strong NE to E trades over the south-central Caribbean and fresh E trades over the Gulf of Honduras to diminish by Fri. Elsewhere, winds and seas will be quiescent through early next week. ...ATLANTIC OCEAN... A dissipating stationary front curves southwestward from a 1019 mb low east of Bermuda across 31N58W to northeast of the Bahamas at 29N74W. Patchy showers and isolated thunderstorms are seen up to 40 nm along either side of this feature. A surface trough over the central and southeast Bahamas is coupling with an upper-level low east of the Florida-Georgia border near 31N77W to trigger scattered showers and thunderstorms from 21N to 26N between 68W and 75W. Another surface trough north of Sao Luis, Brazil near 03N43W is generating widely scattered moderate convection south of 05N between 40W and the coast of Brazil. Convergent trades are creating similar conditions near the coast of Guyana, Suriname and French Guiana. Refer to the Monsoon Trough/ITCZ section for additional convection in the Atlantic Basin. Moderate with locally fresh ENE winds and 4 to 6 ft seas in moderate NE to E swell are found near the stationary front, north of 27N between 65W and the Florida-Georgia coast. Farther southeast, light to gentle E to SE winds and seas of 3 to 5 ft are present from 21N to 27N/31N between 50W and 65W. For the central and eastern Atlantic, light to gentle winds and seas of 5 to 7 ft in moderate N swell are evident north of 20N between the African coast and 50W, including the Canary Islands. To the south, gentle to moderate with locally fresh NNE to NE trades and seas at 6 to 8 ft exist from 03N to 20N/21N between the central African coast and Lesser Antilles. Light to gentle southerly and monsoonal winds with 4 to 6 ft seas prevail for the remainder of the Atlantic Basin. For the forecast west of 55W, the aforementioned stationary front should dissipate later today. A surface trough/low is likely to develop by Fri night and persist through Sun east of the Bahamas. These features should strengthen trades between Bermuda and the Bahamas on Sat and Sun, allowing for fresh to strong winds and building seas peaking near 9 ft, before weakening on Mon. A weak cold front should move off the coast of northeast Florida Sat night, then dissipate north of the Bahamas by Mon. Moderate north swell is anticipated to impact the waters south and southwest of Bermuda east of 60W beginning on Sat. $$ Forecaster Chan