The Atlantic hurricane season runs from June 1st through November 30th. Florida, with its coastlines on both the Atlantic Ocean and the Gulf of Mexico, is highly vulnerable to these storms, experiencing more landfalls than any other U.S. state. While the six-month season is long, the risk is far from uniform, with the vast majority of intense activity concentrated within a much shorter window. Determining the most dangerous time requires looking at the historical frequency and intensity of storms that have impacted the state.
The Month With the Highest Risk
September is the month with the highest risk for hurricanes in Florida. The peak of the Atlantic hurricane season occurs around September 10th, and this is reflected in Florida’s landfall statistics. Historically, nearly one-third of all tropical cyclones that have affected Florida have occurred during September. This month sees the highest frequency of both named storms and major hurricane landfalls, defined as Category 3 or higher. September has produced more Category 5 hurricanes in the Atlantic basin than any other month, making the convergence of favorable atmospheric and oceanic factors the high point for severe storm activity.
Why September Is the Season’s Climax
September’s heightened activity results from ocean and atmospheric conditions reaching their maximum potential for storm formation. The most influential factor is the Sea Surface Temperature (SST), which fuels tropical cyclones. After long summer months of intense solar heating, water across the tropical Atlantic and Gulf of Mexico reaches its warmest point, often exceeding the 80-degree Fahrenheit threshold required for storm development. This deep layer of warm water allows storms to maintain or rapidly increase their intensity.
Atmospheric conditions also align to support storm organization during September. Vertical wind shear, the change in wind speed or direction with altitude, is at its lowest point of the year. Low wind shear is necessary because high shear can tear apart the developing structure of a tropical system, preventing it from strengthening. African Easterly Waves, the primary “seeds” for many powerful storms, are also most active and traversing the Atlantic at optimal latitudes. These waves move westward off the African coast and are often the initial spark for long-track hurricanes that threaten the entire Atlantic basin, including Florida.
Threats During the Rest of Hurricane Season
While September is the statistical peak, the months immediately surrounding it, August and October, still pose a significant threat to Florida. August serves as the major buildup phase, with a high number of named storms beginning to form as water temperatures climb rapidly. Storms in August often begin as long-track Cape Verde types that form far out in the Atlantic, giving forecasters a longer lead time before potential Florida impacts. However, these storms tend to be less intense on average than those that reach their peak in September.
October represents a secondary, dangerous peak as the primary development region shifts closer to the U.S. coast. During this month, storms frequently form in the western Caribbean Sea and the Gulf of Mexico. Storms developing closer to Florida leave less time for preparation, and they can intensify quickly right before landfall. Even outside of this August-to-October core, early-season storms in June and July and late-season storms in November are possible. These systems are generally less common and typically weaker.