The 2011 Atlantic hurricane season was an event in the annual hurricane season in the north Atlantic Ocean. It was well above average, with 19 tropical storms forming. Even so, it was the first season on record in which the first eight storms failed to attain hurricane strength. The season officially began on June 1, 2011, and ended on November 30, 2011, dates that conventionally delimit the period of each year when most tropical cyclones develop in the Atlantic basin. The season's first storm, Tropical Storm Arlene did not form until June 28. The final storm to develop, Tropical Storm Sean, dissipated on November 11.

The 2009 Atlantic hurricane season was an event in the annual tropical cyclone season in the North Atlantic Ocean. It was a below-average Atlantic hurricane season with nine named storms, the fewest since the 1997 season. The season officially began on June 1, 2009, and ended on November 30, 2009, dates that conventionally delimit the period of each year when most tropical cyclones develop in the Atlantic basin. The first storm to form was Tropical Depression One on May 28, 2009, while the last storm, Hurricane Ida, dissipated on November 10.