The National Weather Service in Tampa Bay (Ruskin) evaluated local thunderstorm science and climatology to define the rainy season in our area and to increase public awareness of the associated hazards.
The rainy season in West Central Florida is May 25 to October 10. The rainy season in Southwest Florida, Charlotte, and Lee Counties remains May 15 to October 15.
The rainy season can begin abruptly in some years and the onset can take weeks to develop in other years.
Therefore, the beginning of the rainy season is usually a transition period rather than a single date. The actual start of the rainy season can start before May 25, similar to the way hurricanes can form before the official start of Hurricane Season on June 1.
The summer rainy season is characterized by warm, humid conditions with frequent showers and thunderstorms. The start date of the rainy season varies from year to year. It is largely determined by the onset of almost daily showers and thunderstorms over the Florida peninsula and night and morning showers and thunderstorms over the waters in the Gulf of Mexico.
This is typically accompanied by an increase in humidity with persistent dew point values above 70F, daily low temperatures in the 70s to around 80, and high temperatures in the upper 80s to the mid-90s.
The rainy season usually has three phases:
- Late May through early July is the “stormiest” part of the season. Severe weather impacts include damaging winds, waterspouts, tornadoes, excessive lightning, hail, and flooding rain.
- Early July through early September remains hot, humid, and wet
- Mid-September through early October tends to have higher rainfall variability due to potential tropical systems and early-fall cold fronts.
The 3-month temperature and precipitation outlook for June, July, and August will be available from the Climate Prediction Center on May 15 at https://www.cpc.ncep.noaa.gov.