Atlantic Tropical Weather Discussion
NOAA National Hurricane Center (NHC) issues tropical cyclone advisory products at least every 6 hours at 5 am, 11 am, 5 pm, and 11 pm EDT.
Expires:No;;186008 AXNT20 KNHC 181745 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1815 UTC Sat Jul 18 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 1200 UTC surface analysis and satellite imagery through 1745 UTC. ...SPECIAL FEATURE... Caribbean Gale Warning: A tight pressure gradient between the western Atlantic high pressure ridge north of the basin along 27N-28N, and the Colombian low will continue to support NE to E winds strong to near-gale force winds today, pulsing to gale- force across the waters N of Colombia tonight. Otherwise, strong to near- gale force trade winds and rough seas will prevail across the much of the central Caribbean into early Mon before contracting to south of 15N. Rough to very rough seas in the 12 to 14 ft range will develop during the times of peak winds. Please read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave is along 30W, south of 19N, moving westward near 15 kt. Isolated moderate convection is observed along the wave axis. A central Atlantic tropical wave is along 53W, south of 17N, moving westward at 20 kt. Scattered moderate convection is noted from 07N to 10N between 50W and 57W. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic near 20N16.5W and continues southwestward to 08N40W. The ITCZ extends from 08N40W to 07N52W. Scattered moderate to isolated strong convection is present from 09N to 14N east of 23W. ...GULF OF AMERICA... Upper level low pressure across Florida and the far eastern Gulf during the past 48 hours extends into the lower atmosphere, and a weak surface trough is now across the Gulf along 83W-84W. The upper low and abundant low level moisture are resulting in scattered strong showers and thunderstorms over the E Gulf waters, N of 23N and E of 87W. These storms can produce gusty winds, frequent lightning and suddenly higher seas. Mariners should exercise caution across this area. This system has a medium formation chance through 7 days. Elsewhere, 1020 mb high pressure centered south of Louisiana dominates the basin, supporting moderate NW winds west of the trough and moderate to fresh E winds over the Bay of Campeche. Elsewhere, light to gentle winds and slight seas prevail. For the forecast, a low offshore Florida will drift north over the next few days, bringing thunderstorms with heavy rain to the eastern Gulf. There is a low chance of tropical formation with this system. Elsewhere, weak high pressure will dominate, producing gentle to moderate winds and slight to moderate seas through the period. ...CARIBBEAN SEA... A Gale Warning remains in effect for the south-central Caribbean near the coast of Colombia. Please refer to the Special Features section for more details. Winds are expected to peak to gale force tonight. The 1025 mb subtropical ridge centered near 29.5N57W in the central Atlantic extends westward to the Bahamas, and is forcing strong to near gale-force easterly trade winds across the central Caribbean, with the strongest winds occurring off Colombia and in the Gulf of Venezuela. Recent satellite scatterometer data showed peak winds of 30 kt. Rough to very rough seas to 14 ft are found in these waters. Fresh E winds and seas of 6 to 8 ft are present in the eastern Caribbean. Elsewhere, light to gentle winds and slight to moderate seas are prevalent. Scattered showers are found across the SE Caribbean waters. For the forecast, the pressure gradient between the Atlantic high pressure ridge axis oriented along 27N-28N and the Colombian low will support NE winds pulsing to gale-force across the waters N of Colombia early tonight. Otherwise, strong to near- gale force trade winds and rough seas will prevail across the much of the central Caribbean into early Mon, before contracting to south of 15N. East winds will pulse fresh to locally strong each evening this weekend in the Windward Passage. ...ATLANTIC OCEAN... A weak surface trough in the north-central tropical Atlantic supports isolated showers north of 25N and between 35W and 50W. Meanwhile, a broad subtropical ridge centered over the central Atlantic extends westward along 27N-28N to the Bahamas, and sustains moderate to fresh easterly winds and seas of 4-8 ft south of 25N and west of 35W, with highest winds and seas between 52W and the Lesser Antilles. In the far eastern Atlantic, moderate winds and seas of 4-7 ft are noted north of the monsoon trough and east of 35W. Moderate to locally fresh S to SW winds and seas of 4-7 ft are evident south of the monsoon trough and east of 35W. Elsewhere, moderate or weaker winds and moderate seas prevail. For the forecast west of 55W, the western Atlantic subtropical ridge axis that extends along 27N-28N will gradually weaken and drift northward this weekend as a broad surface trough forms E of 50W. This trough will shift westward and reach 65W by Wed. Moderate to fresh trades will prevail S of 24N, with gentle winds to the N. Pulsing strong winds are expected during the evenings this weekend N of Hispaniola and in the Windward Passage. $$ KRV |