Timeline of the 1990 Atlantic hurricane season

The 1990 Atlantic hurricane season consisted of the events that occurred in the annual cycle of tropical cyclone formation over the Atlantic Ocean north of the equator. The season officially began on June 1, and officially ended on November 30. These dates, adopted by the convention, historically delimit the period each year when most Atlantic tropical systems form. However, storm formation is possible at any time of the year, as was the case this season, when Tropical Depression One formed on May 24; Hurricane Nana, the season's final system, dissipated on October 21. Overall this year, 16 tropical cyclones formed within the basin, of which 14 became named storms; 8 of those became hurricanes, of which 1, Hurricane Gustav, became a major hurricane.

This timeline documents tropical cyclone formations, strengthening, weakening, landfalls, extratropical transitions, and dissipations during the season. It includes information that was not released throughout the season, meaning that data from post-storm reviews by the National Hurricane Center, such as a storm that was not initially warned upon, has been included.

The time stamp for each event is first stated using Coordinated Universal Time (UTC), the 24-hour clock where 00:00 = midnight UTC. The NHC uses both UTC and the time zone where the center of the tropical cyclone is currently located. The time zones utilized (east to west) prior to 2020 were: Atlantic, Eastern, and Central. In this timeline, the respective area time is included in parentheses. Additionally, figures for maximum sustained winds and position estimates are rounded to the nearest 5 units (miles, or kilometers), following National Hurricane Center practice. Direct wind observations are rounded to the nearest whole number. Atmospheric pressures are listed to the nearest millibar and nearest hundredth of an inch of mercury.