That's not rain on the radar – it's bugs


No that wasn't rain on the weather radar.

The National Weather Service in La Crosse tweeted a radar loop from 9:40 p.m. Wednesday night, showing what appears to be one of the first mayfly hatches of the season along the Mississippi River in southern Minnesota.

That's right. There were so many mayflies it could be seen on the radar.

This is a pretty common occurrence along the river this time of year, according to the National Weather Service in La Crosse, which tracks mayfly hatches. A few times a year, the bugs emerge from the river as adults, find a mate, drop their eggs back into the water, and then die soon after.

Some years the hatches are bigger than others. The last "massive emergence" of mayflies was on July 20, 2014, when there were so many mayflies flying around it made it hard to see.

And if they all die in the same place, their dead bodies can make roads slippery. In fact, the dead bugs caused a driver to lose control and crash in Wisconsin that year. In other years, snowplows have been called in to clear the dead bugs off the road.

The crazy amounts of bugs covering everything in your neighborhood can be pretty gross, but an abundance of these harmless insects is a good thing. Mayflies only hatch from waterways with high-quality water, the Minnesota DNR's website says.

So at least we know the river is clean, right?

And if you're not grossed out yet, check out this video of a bunch of dead mayflies outside of a Dunkin' Donuts in Prairie du Chien, Wisconsin, early Thursday morning.

Here are some more mayfly photos:

Posted by Jim Little on Thursday, July 6, 2017


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