000 AXNT20 KNHC 281746 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Tue May 28 2024 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. ...TROPICAL WAVES... A tropical wave is in the eastern Atlantic along 23W, south of 12N, moving westward at 15 to 20 kt. Scattered moderate to isolated strong convection is observed where the wave meets the ITCZ and mainly from 02N to 08N between 20W and 30W. A second tropical wave is along 50W, south of 11N. The wave is moving westward at around 20 kt. Scattered moderate to isolated strong convection is noted mainly ahead of the wave axis from 04N to 07N between 50W and 55W. This convective activity is affecting parts of French Guiana and Suriname. A tropical wave is moving westward at 10 to 15 knots across the central Caribbean Sea. Its axis is along 74W, south of 21N, extending across from the Turks and Caicos Islands across Haiti into northern Colombia. Latest scatterometer data captured the wind shift related to the wave axis as well as moderate to fresh winds associated with it. This system continues to generate some shower and thunderstorm activity over parts of Hispaniola and regional waters. Moisture associated with this wave will continue to spread into Jamaica and eastern Cuba through at least Wed. The storm activity may produce gusty winds and locally heavy rain. Please refer to your local weather office for more specific information. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through the coast of Senegal near 14N17W and continues southwestward to 08N20W to 05N30W. The ITCZ extends from 05N30W to 04N40W to 05N49W. Most of the convective activity across the area is associated with the tropical waves. GULF OF MEXICO... A cold front is clipping the far NE Gulf. A weak ridge dominates most of the Gulf waters while a surface trough is analyzed W of the Yucatan Peninsula. The pressure gradient between the ridge and lower pressures over Texas and Mexico is resulting in mainly gentle to moderate SE winds across most of the basin, with the exception of light and variable winds over the NE Gulf. Seas are 3 to 5 ft W of 88W and 1 to 3 ft elsewhere. Hazy conditions due to agricultural fires in Mexico persist across most of the western Gulf, including the Bay of Campeche where dense concentration of smoke is noted on the smoke graphic recently issued by SAB. Visibilities are 3 nm or less across many observing sites along the SW and western Gulf coast. The above mentioned trough usually develops during the evening hours over the Yucatan Peninsula and drifts westward over the SW Gulf during the night and morning hours where it dissipates before redeveloping again in the evening over the Yucatan Peninsula. For the forecast, weak surface ridging will continue to dominate across the Gulf through Sat. As a result, winds will be SE gentle to moderate west of 87W through Thu, but become moderate to fresh Wed evening through Sat night. A weak cold front will move across the far NE Gulf today, followed by gentle W to NW winds. Otherwise, fresh to strong NE to E winds will pulse near the N and W portions of the Yucatan peninsula during the late afternoons and at night for the next several days. Haze west of 87W due to agricultural fires over Central America and Mexico will continue for at least the next couple of days. Visibilities will be 3 NM or less in the SW Gulf of Mexico. CARIBBEAN SEA... Please read the Tropical Waves section for details on the tropical wave currently moving across the central Caribbean Sea. The persistent upper-level trough continues to shift westward across the western Caribbean. Its axis now extends from east- central Cuba to near the Nicaragua/Honduras border. This feature continues to transport abundant tropical moisture northward from the SW Caribbean to across Hispaniola and into the Atlantic, enhancing convection across the area. An area of numerous showers and thunderstorms has developed ahead of the trough axis over the SW Caribbean. This convective activity is reaching the coasts of Costa Rica and Nicaragua. Recent scatterometer data indicate fresh to strong winds in association with this convective activity, particularly S of 15N and W of 80W. Gusty winds to near gale-force are likely occurring. Low topped trade wind showers are noted elsewhere, while a dense concentration of smoke persists over the Gulf of Honduras due to agricultural fires over northern Central America. Visibilities are 3 NM or less along the northern coast of Honduras and the Bay Islands. High pressure north of the Greater Antilles is promoting moderate to fresh easterly trade winds over much of the eastern and central Caribbean and also west of 84W. Seas in these waters are 4 to 6 ft, except 5 to 7 ft over the south-central Caribbean near the coast of Colombia. Fresh to strong winds are noted in the vicinity of the ABC Islands. Elsewhere, moderate or weaker winds and slight to moderate seas prevail. For the forecast, a moderate pressure gradient between the Bermuda High north of the area and lower pressure along N South America will force fresh to strong trades over the S central Caribbean and Gulf of Honduras through Wed. Winds will become moderate to fresh Thu through the weekend. A tropical wave currently over the central Caribbean is causing scattered showers and thunderstorms as it moves slowly westward during the next couple of days. Smoke from agricultural fires over Central America is causing reduced visibilities over the Gulf of Honduras. ATLANTIC OCEAN... Two tropical waves are noted between the coast of Africa and the Lesser Antilles. Please, read the Tropical Waves section for more details. A ridge dominates the Atlantic forecast waters E of 50W, anchored by a 1026 mb high pressure system located E of the Azores near 37N19W. A surface trough extends from 31N65W to 20N60W. Scattered showers and thunderstorms are ahead of the trough affecting the waters N of 28 between 45W and 50W. W of this trough another ridge is observed extending towards the SE Bahamas and the Turks and Caicos Islands. Recent satellite derived wind data indicate the presence of a pre-frontal a trough just E of Florida generating some shower and thunderstorm activity. Gentle to moderate winds dominate most of the waters N of 20N with seas of 3 to 5 ft while moderate to fresh trades are seen across the tropical Atlantic with seas of 5 to 7 ft. The pressure gradient slightly tightens just N of the Cabo Verde Islands between the ridge and low pressures over W Africa. As a result, an area of fresh to locally strong NE winds extends from the Cabo Verde Islands to about 23N and E of 30W to the coast of W Africa. Seas are 6 to 8 ft in this area. For the forecast W of 55W, a 1029 mb Bermuda High is contributing toward moderate or lighter winds across the basin, except for moderate to fresh SW winds across the offshore zones N of 27N. The moderate winds are due to a weak cold front forecast to emerge from the SE United States coast tonight. Scattered showers and thunderstorms will accompany the front. The front will move eastward toward the Greater Antilles later this week and into this weekend, bringing moderate to fresh winds. Otherwise, winds and seas away from the thunderstorms should remain quiescent for the next few days across the forecast waters. $$ GR