The 1965 Atlantic hurricane season was the first to use the modern-day bounds for an Atlantic hurricane season, which are June 1 to November 30. These dates conventionally delimit the period of each year when most tropical cyclones form in the Atlantic basin. It was a slightly below average season, with 10 tropical cyclones developing and reaching tropical storm intensity. Four of the storms strengthened into hurricanes. One system reached major hurricane intensity – Category 3 or higher on the Saffir–Simpson hurricane scale. The first system, an unnamed tropical storm, developed during the month of June in the southern Gulf of Mexico. The storm moved northward across Central America, but caused no known impact in the region. It struck the Florida Panhandle and caused minor impact across much of the Southern United States. Tropical cyclogenesis halted for over two months, until Anna formed on August 21. The storm remained well away from land in the far North Atlantic Ocean and caused no impact.

The Atlantic hurricane season is the period in a year, from June 1 through November 30, when tropical or subtropical cyclones are most likely to form in the North Atlantic Ocean. These dates, adopted by convention, encompass the period in each year when most tropical cyclogenesis occurs in the basin. Even so, subtropical or tropical cyclogenesis is possible at any time of the year, and often does occur.