PITTSBURGH (KDKA/CNN) — They have arrived, and Ohio residents say the mayflies have arrived in force.

Mayflies are covering homes, cars, and everything in their path along Lake Erie.

Photo Credit: Tony White/Facebook via WOIO

Photos posted to social media show one person’s car completely covered in mayflies.

The car is in a parking lot at Miller Ferry, the boat that takes people back and forth from Put-in-Bay, Ohio.

The mayflies were so bad, they were even caught on weather radar.

Cleveland meteorologist Kelly Dobeck posted photos of home covered in mayflies Thursday morning.

These mayflies come from the waters of Lake Erie. According to the Ohio Sea Grant research and education program, the mayflies begin as eggs burrowing in lake sediment, and after a year or two, they swim to the surface, emerging fully winged. Adult mayflies vary in size from a quarter-inch to an inch long.

Photo Credit: CNN

They won’t be around for long, though. Individual mayflies live up to two days once they come on land. The swarms typically last about a month.

Residents may find them annoying, but the mayfly swarm is an indication of good water health in the Great Lakes, according to Ohio Sea Grant.