Hurricane Isidore was a powerful tropical cyclone that caused widespread flooding and heavy damage across Mexico, Cuba, and the United States in September 2002. The ninth named storm and the second hurricane in the 2002 Atlantic hurricane season, and the fifth of eight named storms to occur in September of that year, Isidore peaked as a Category 3 hurricane, causing damage, as well as four fatalities in Jamaica, Cuba, Mexico, and the United States. Isidore is also noted for threatening to strike the northern Gulf Coast as a Category 4 hurricane, however, the storm struck the region as a moderately-strong tropical storm, due to a track change that brought the storm over the Yucatán Peninsula for over a day, which significantly weakened the cyclone in the process. The primary impact from the storm was the heavy rainfall, which fell across southeast Mexico, and also from the central United States Gulf coast into the Ohio Valley.

The 2002 Atlantic hurricane season was a near-average Atlantic hurricane season. It officially started on June 1, 2002, and ended on November 30, dates which conventionally limit the period of each year when most tropical cyclones develop in the Atlantic Ocean. The season produced fourteen tropical cyclones, of which twelve developed into named storms; four became hurricanes, and two attained major hurricane status. While the season's first cyclone did not develop until July 14, activity quickly picked up: eight storms developed in the month of September. It ended early however, with no tropical storms forming after October 6—a rare occurrence caused partly by El Niño conditions. The most intense hurricane of the season was Hurricane Isidore with a minimum central pressure of 934 mbar, although Hurricane Lili attained higher winds and peaked at Category 4 whereas Isidore only reached Category 3. However, Lili had a minimum central pressure of 938 mbar.