MOLINE, Ill. — Flies and other flying insects can interrupt our enjoyment of the great outdoors, especially before certain weather events arrive. You aren't wrong in thinking that their activity is quite sporadic. Everything from temperature to pressure can impact how active these little buggers are.
Scott from Osco, Illinois, asked, "Is it true that when flies are pesky and biting it means rain is coming?" Let's dig in!
Not an old wives' tale
Our sister station, WFMY in Greensboro, North Carolina, spoke to a local biologist regarding flying insect activity in weather.
Frank Fowler, a biologist with McNeely Pest Control, said he always heard that biting flies mean pending rain. He had thought it was an old wives tale until he started studying insects.
He explained many animals can detect changes in weather before they occur and respond by taking shelter. The lower barometric pressure preceding a storm can cause animals to want to feed. Thus, flies sometimes bite humans to get blood.
Older generations tended to spend more time outside than working adults today, so they knew when the flies started biting, rain was probably on the way.
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Mosquitoes are a bit more picky
According to Orkin, conditions that affect mosquito activity include wind, temperature, relative humidity, rainfall and drought conditions.
Wind: Flying is not a strong suit for these insects. The less wind, the better.
Temperature: Most species of mosquitoes thrive when temperatures are close to 80°F
Humidity: Higher relative humidity will spur more mosquito activity.
So, the next time flying insects are pestering you, grab an umbrella and prepare for rain in the near future.
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