Atlantic Tropical Weather Discussion
148 AXNT20 KNHC 171033 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1215 UTC Mon Aug 17 2026 Tropical Weather Discussion for North America, Central America Gulf of America, 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 1020 UTC. ...TROPICAL WAVES... A tropical wave is in the eastern Atlantic along 18W, south of 20N, based on satellite data and tropical wave guidance. The wave is moving westward at 10 to 15 kt. Scattered moderate convection is observed from 07N to 18N between 13W and 25W. A tropical wave is in the central Atlantic with axis near 38W, extending from 02N to 18N, and moving westward at 15 kt. Scattered moderate convection is from 08N to 10N between 35W and 40W. A tropical wave is E of the Lesser Antilles with axis near 57W, south of 18N, moving westward at 15 to 20 kt. Scattered moderate convection is noted from 10N to 18N between 51W and 61W. A tropical wave is in the W Caribbean with axis near 78W, south of 20N, and moving westward at 15 kt. Numerous moderate to strong convection is ahead of the wave axis and over the Nicaragua, Costa Rica and Panama offshore waters. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through 18N16W and continues southwestward to 13N30W to 11N43W. The ITCZ extends from 11N43W and continues to 14N52W to 11N61W. No significant convection is evident aside from the convection discussed in the Tropical Waves section above. ...GULF OF AMERICA... High pressure dominates the Gulf waters, supporting light to gentle variable winds and slight seas N of 24N. Moderate to locally fresh NE to E winds are in the SW basin due to a westward moving through in the Bay of Campeche, which is also supporting moderate seas to 6 ft. Moderate NE to E winds are also in the Florida Straits and the approaches to the Yucatan Channel. For the forecast, high pressure will prevail across the Gulf waters through the week. A weak pressure gradient will support mostly gentle to moderate winds across much of the basin. A diurnally induced surface trough will generate fresh to occasionally strong winds N of the Yucatan peninsula early each evening. These winds will spread westward away from the Yucatan at night as the trough migrates into the SW Gulf. Slight to moderate seas are expected through the forecast period. ...CARIBBEAN SEA... A tropical wave over the SW Caribbean is supporting heavy showers and tstms across the Central America offshore waters and is also associated with fresh to strong winds affecting most of the central and portions of the SW Caribbean where seas are rough to 10 ft. Elsewhere, winds are moderate to fresh from the NE to E and seas are moderate, including the Windward Passage. Gentle to moderate NE to E winds are elsewhere in the NW Caribbean, except for fresh winds in the lee side of Cuba. For the forecast, the pressure gradient between the ridge N of the area and the Colombian low will support fresh to strong winds over the central Caribbean though late today. Fresh to strong winds over the central basin will resume Wed night through Fri night as high pressure redevelops E of the Bahamas. A tropical wave with axis near 78W will continue to move across the western Caribbean through Tue before moving W of the region. ...ATLANTIC OCEAN... A cold front extends from a 1009 mb low pressure system near 33N54W to 31N54W to 27N63W to 31N71W. Fresh to strong SW winds are ahead of the front N of 28N and E of 58W. Scattered showers and tstms are within 240 nm ahead of the front. The central and eastern subtropical Atlantic is under the influence of a 1026 mb high pressure system centered N of the Azores, which is supporting moderate or weaker winds and moderate seas, except for moderate to fresh NE winds E of 20W. For the forecast west of 55W, surface ridging along 27N and the passage of a pair of tropical waves across the Caribbean Sea will modulate moderate to fresh NE to E winds south of 23N through the forecast period. Otherwise, the cold front will continue to move across the northern forecast waters today then stall and weaken into a trough by Tue. Fresh to strong SW to W winds ahead of the front will diminish by this evening. However, shower activity associated with the front and its remnants is forecast through Thu.