On the Gulf Coast, subterranean termite swarm season runs from late winter through early summer. Asian subterranean termites tend to fly first (mid-February into spring), and the destructive Formosan subterranean termite peaks from April through June, usually on warm, humid evenings. Seeing winged termites or shed wings indoors means a mature colony is nearby — and because our winters are mild, termites keep feeding nearly year-round, so protection shouldn't wait for spring.
Swarming is tied tightly to species and weather. Long-term monitoring in the Southeast found distinct but overlapping flight seasons: the Asian subterranean termite from about mid-February to late April, and the Formosan subterranean termite from early April to late June. In the broader Gulf region, mass Formosan swarms concentrate in May and June.
Temperature is the trigger. Low temperature is the single biggest factor suppressing flights — when it's cool, termites don't fly. Once colonies are mature, swarms break out on warm, humid evenings, frequently after rain.
Survey records show Mobile and Baldwin counties carry Alabama's highest concentration of Formosan infestations, where the species is considered widespread. Across the state line, monitoring confirms Formosan termites are now established in most of Florida's coastal counties. Warm temperatures and high humidity — exactly our climate — let these colonies thrive.
Yes. While swarms are a spring-and-early-summer event, the colonies feed far longer. Research found subterranean termites keep feeding through mild winters as long as average soil temperatures stay above about 59 F (15 C), and only prolonged cold slows them. On our coast, soil rarely stays that cold for long — so a Sentricon-style baiting and monitoring program works nearly year-round.
When do termites swarm in coastal Alabama and Northwest Florida? Late winter through early summer. Asian subterranean termites fly mid-February into spring; Formosan termites peak April through June on warm, humid evenings.
What triggers a termite swarm? Warmth and humidity. Cool temperatures suppress flights, so swarms happen on warm, humid evenings, often after rain.
Are Formosan termites common on the Gulf Coast? Yes. Mobile and Baldwin counties have Alabama's highest concentration, and Formosan termites are now established in most coastal Florida counties.
Does termite baiting work in winter? Largely yes. Termites keep feeding while soil stays above about 59 F (15 C); only prolonged hard cold slows them, so bait monitoring continues nearly year-round here.
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