This same weekend five years ago saw one of the more significant flooding events in our area. Many locations picked up well over a foot of rain over a three day period. All that rain in such a short period of time created significant flooding. The flood waters inundated homes, roadways, and even caused mudslides.
Below is a rainfall total map of the area. Notice these are rainfall estimates from the radar in La Crosse. That’s why, as the yellow circle highlights, the radar causes a break in the 10-12 inch rainfall totals.
The highest observation was down in Witoka, MN where they picked up 17” of rain. The La Crosse airport picked up nearly 7”. So where did all that water come from? Also, why did all the heavy rain fall in such a narrow and long band? Check out the image below.
That Saturday, a warm front set up shop in northern Iowa and just sat there through Sunday. A very warm and moist air mass rode up over the front and fueled showers and storms. With so much moisture in place, the storms were capable of very heavy rainfall. When the storms developed on Saturday, the rode along the warm front and continued to develop over the same areas. This is known as “training.”
As a result of all the rain many local rivers ran well above flood stage with some even reaching new records. Below are several pictures from that weekend. Interesting 5 years later these areas are under drought.