National Weather Service United States Department of Commerce

Overview

Rainfall and flooding of historic proportions struck parts of the Upper Mississippi River Valley on Saturday night, August 18th, continuing through Sunday, August 19th. Rainfall in excess of 15 inches fell in some areas, with the main swath of heaviest rain centered along a line from Claremont and Rochester, Minnesota to La Crosse, Viroqua and Muscoda, Wisconsin.  A 24-hour rainfall record was set for the state of Minnesota near Hokah, MN (Houston Co.) with 15.10 inches, while unofficial readings may have exceeded 17". 

There were numerous mud slides, roads washed out, and flash flooding that killed 7 people. The community of Rushford, MN was flooded by Rush Creek and infrastructure remained damaged for months.  Damage costs likely exceeded $200 Million.

 

Weekend Rainfall Totals from August 18th-19th
Witoka, MN
17.00"
La Cresent, MN
11.58"
Zumbro Falls, MN
8.14"
Utica, MN
14.00"
Rochester, MN (northwest side)
11.10"
Valley, WI
7.25"
New Hartford/Nodine, MN
13.40"
Viroqua, WI
9.73"
Rochester Airport, MN
7.05"
Stoddard, WI
12.41"
Dodge Center, MN
9.07"
La Crosse Airport, WI
6.99"
La Crosse, WI (south side)
12.20"
Westby, WI
8.05"
Theilman, MN
6.33"
setup map
Rushford, MN during the flooding
(Photo by Jeff Thompson)

Why did it happen?

A stalled frontal boundary acted as the focus for continuous redevelopment of showers and thunderstorms throughout the weekend. A moist and warm air mass rose up and over this boundary, providing the fuel for the rain. Due to the training nature of the storms, heavy rain persisted hour after hour across southeast Minnesota into southwest Wisconsin, with rainfall rates of 1 to 2 inches per hour common.

nws logo Media use of NWS Web News Stories is encouraged!
Please acknowledge the NWS as the source of any news information accessed from this site.
nws logo