Termite "swarmers" are winged termites that fly away from their colonies in search of a place to start a new colony. When termites swarm depends on the species of termite, the geographic location of the colony and weather. Eastern subterranean termites, one of the most common types of termite that infest homes in the U.S., usually swarm in the spring following rain, first in the more southern states and then further north as temperatures rise.