The Formosan Termites in New Orleans and the SouthEast US produce winged reproductives that swarm during the months of April through July. The largest swarms typically appear in May. Many of the termites come from nests that are in outdoor trees or shrubs. Inspection to find the source of a swarm can help locate nests.
Flying termites are attracted to light, a behavior considered to be an adaptation for the winged reproductives to escape the confines of their dark, light-blocking tunnels to reach the twilight and open air. People are advised to turn off their lights from dusk until about midnight to prevent them from being attracted to a structure. The timing of the swarms is correlated with warm humid nights and days with afternoon showers.