Where Thunderstorms Happen

Some places regularly experience more thunderstorms than others. Some can even have multiple thunderstorms in a single day. Why are some places stormier than others?

The amount of moisture in the air and the air temperature determine how often thunderstorms form at a particular location. Geographic location also plays a role. Formation of cumulus clouds, which can lead to thunderstorms, often creates conditions for thunder and lightning to form as electric charges accumulate within the clouds.

To determine which places have more thunderstorms than others, scientists record the number of days thunder is heard, and also the number of days lightning strikes are seen, at weather stations across the country. The map below shows the number of days with thunderstorms per year in the contiguous United States.

Map of the United States titled Average Number of Thunderstorm Days Per Year.  According to this map, the greatest incidence of thunderstorms occurs in the southeast United States, indicating that there are 70-90 days with thunderstorms per year that occur in Florida and the southern-most portions of Alabama and Mississippi.  A stretch of Floria between Southwest Florida moving north averages more than 90 days with thunderstorms per year.