JS Online:Radar image has some bugs in it, literally: "So what was it last Friday that turned the radar in the La Crosse area into a sea of white?
It turns out that it was a gigantic hatch of mayflies.
The bugs were so thick that they showed up as a rainstorm of mayflies on National Weather Service radar.
For about 1 1/2 hours starting at 9 p.m., the insects drifted north, with the radar showing them blanketing areas along the Mississippi River."
CNN does the math
33 minutes ago