Atlantic Tropical Weather Discussion
240 AXNT20 KNHC 180428 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0615 UTC Sun Oct 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 0000 UTC surface analysis and satellite imagery through 0400 UTC. ...SPECIAL FEATURES... Gulf of America Gale Warning: A cold front extends across the southern Gulf tonight from near Naples, Florida, to 21N94W, then is nearly stationary southward across the central Bay of Campeche to the Mexican coast along 93.5W. Strong high pressure dominates most of the eastern U.S. and extends across the Gulf behind the front. This is forcing near storm-force NW winds behind the front from Coatzacoalcos to offshore of Veracruz, Mexico, where seas have built to 18-22 ft. A broader area of gale force winds and very rough seas are present behind the front offshore Mexico from Tampico to the central Bay of Campeche. Frequent gusts in excess of gale force are occurring within 90 nm of the NE Gulf coast, where a Gale Warning is also in effect. Elsewhere across the Gulf NE to N winds of 20 to 30 kt prevail, with seas of 8 to 15 ft. These gales will continue into Mon morning, before the cold front clears the basin and winds begin to diminish. Peak seas may exceed 25 ft in the Bay of Campeche late tonight and Sun, with rough seas prevailing across large portions of the basin through Tue. Atlantic Gale Warning: This same cold front continues to move SE across the western Atlantic waters, and extends from 31N75W to the SE Florida coast near Lake Worth and across S Florida. Recent satellite scatterometer data shows N winds 20 to 30 kt behind the front, with frequent gusts over gale-force N of 28N and west of 75W, where a Gale Warning is in effect. Seas behind the front have built quickly to 8 to 12 ft. The front will reach from 31N72W to the Straits of Florida by early Sun morning, and from near 31N70W to western Cuba by early Mon morning, then stall and dissipate through mid week. Gale-force gusts are expected to continue across the northwestern zones through Sun. Seas behind the front are expected to build to 10 to 18 ft in N to NE swell on Sun, and higher in the Gulfstream. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZNT02 KNHC/HSFAT2 or at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for further details. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the African coast near 11N15W to 08.5N16W. The ITCZ then extends from 07N17W to 05.5N32W to 10N44W. Scattered moderate convection is occurring from 04N to 07N and E of 17W. Scattered to locally numerous moderate isolated strong convection is noted from 07N to 12.5N between 36W and 55W. ...GULF OF AMERICA... See Special Features section above for information on the Gale Warnings in effect for portions of the Gulf of America and the western Atlantic, behind a cold front. Scattered to locally numerous showers and isolated thunderstorms are present along and within 60- nm S of the cold front, from SW Florida to the Bay of Campeche. Recent buoy data shows seas are 7 to 12 ft to the N of 25N and much higher across the SW Gulf, as described above. Moderate to fresh NE winds prevail south of the front across the SE basin and the eastern Bay of Campeche, where seas are 3 to 6 ft and higher near the front. For the forecast, the front will continue to move southeastward, and slow down its forward progress as it reaches from the Florida Straits to Merida, Mexico by early Sun, then drift to the southeast of the Gulf through Tue as it weakens. Gale-force winds off Veracruz will persist over the SW Gulf through Sun night, with sea subsiding below 20 ft. Gales will diminish in the west- central Gulf by early Sun, and frequent gusts to gale force elsewhere behind the front should diminish by Sun early in the afternoon. Strong NE winds and rough seas will persist elsewhere north of the front into early next week. Looking ahead, strong high pressure will build over the lower Mississippi Valley behind the front, maintaining fresh NE to E winds mainly over the eastern half of the Gulf into mid-week. ...CARIBBEAN SEA... Deep-layer moisture is interacting with an upper-level trough across the Yucatan Channel and Peninsula to produce divergence is inducing scattered moderate convection across the Gulf of Honduras south of 18N. Meanwhile, favorable upper level conditions are supporting numerous showers and thunderstorms occurring in a 180 nm wide band from NE Colombia to the Honduras-Nicaragau border. To the east and northeast, a broad upper trough is producing very stable conditions, and fair skies. At the surface, moderate to fresh trades prevail across the central basin between 64W and 78W, where seas are 4 to 6 ft. Elsewhere gentle to moderate easterly trades and moderate seas prevail. For the forecast, as the cold front has moved across the Western Atlantic and the Gulf of America, the pressure gradient across the Caribbean has relaxed, supporting moderate to fresh winds offshore Colombia and in the Gulf of Venezuela. Moderate or weaker winds and slight to moderate seas are forecast elsewhere through Thu. An area of showers and thunderstorms associated with a surface trough will continue to affect the NW Caribbean tonight. The Gulf of America cold front will likely reach western Cuba and the Yucatan Channel by Tue then gradually dissipate. Large seas in northerly swell associated with the front are expected to move through the Yucatan Channel with hazardous conditions midday Sun into early Tue. ...ATLANTIC OCEAN... See Special Features section above for information on a Gale Warning for waters offshore NE Florida. Scattered to locally numerous moderate isolated strong convection is ongoing along and E of the cold front extending from 31N75W to the SE Florida coast near Lake Worth. Convection is generally occurring from the cold front to the NW Bahamas and then northeastward to near 31N70W. Light SE to S winds and seas 4 ft or less prevail E of the front to 65W. More scattered moderate isolated strong convection extends from 19N to 29N between 45W and 57W, in association with a deep- layer trough across that area. Further to the east, a broad area of scattered moderate convection is noted from 13N to 25N between 32W and 42W, in association with another deep-layer trough. Strong high pressure located NW of the Azores extends a broad ridge southwestward to the central Bahamas, but drapes across a series of surface troughs from 20N and 30W between 38W and 60W. The pressure gradient N of these trough is yielding moderate to fresh easterly winds with seas of 6 to 8 ft in N swell. S of the area, southward of 25N, gentle to moderate easterly trades prevail across the Tropical Atlantic, where seas are 4 to 6 ft between 30W and 65W. Moderate to locally fresh NE to E winds and seas of 5 to 7 ft are found N of 20N and E of 30W to Africa, with gentle to moderate winds and seas found there S of 20N. For the forecast west of 55W, the strong cold front will continue to move southeastward and reach from 31N72W to the Straits of Florida by early Sun morning, and from near 31N70W to western Cuba by early Mon morning, then stall and dissipate through mid week. Strong to near-gale force winds and very rough seas to 18 ft will follow the front, affecting mainly the waters west of 65W through Tue. Associated northerly swell will linger through much of the week.