Termite swarm risk in California Polytechnic State University, CA

Swarms on warm spring days, usually in daylight and often within a day or two of rain, as the soil warms.

Swarms at dusk on warm, humid, still evenings in late spring and early summer, the massive flights the Gulf Coast is known for.

Needs no soil contact, so flights come straight out of dry structural wood. In the Southeast, Gulf, and Florida it swarms at night in spring and early summer; in California and Arizona it swarms on warm late-summer and fall days.