On July 20, 2014, a massive hatching of mayflies emerged from underwater and then, like a good SciFi movie, began to wreak havoc across Wisconsin, Iowa and Minnesota. At the outset, the Mississippi River produced a huge radar echo, as the mayflies emerged from the water and became airborne.
According to the National Oceanic and Atmospheric Administration (NOAA) and the National Weather Service, the radar detected the flies about 8:45 p.m., coming from the river with echo values much like light to moderate rain. There was a south-to-north wind flow above the water's surface, and the mayflies took flight and quickly moved north.
Following are some scenes from the mayfly mayhem in Wisconsin and Minnesota.
Like a stock market gone bad, it was a flight to cash for this swarm descending on an ATM.
Cass Street Bridge, in La Crosse, Wisc., had some unwelcome pedestrians.
Parking lots became mayfly lots.
This gas station became an insect-themed Edward Hopper painting.
A streetlamp draws in the mayflies.
This blue heron statue was under attack.
A sidewalk view shows some of the swarm up close.
A patio took on an air of foreboding.
Yet another reason why it's always best not to let the gas tank get too empty.
The mayflies bang against a building window.