Thunderstorms can occur year-round and at all hours.
However, they are most likely to occur in the spring and summer months, especially from May through August.
The formation of thunderstorms requires warm, moist air, such as the tropical air masses that come from the Gulf of Mexico and move across the United States.
Thunderstorms usually develop at the time of day when the surface air is the warmest, which is generally around 2 to 4 pm.
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