Flash Flood — Vernon, Wisconsin

2018-08-27 to 2018-08-28 · near Victory, Vernon, Wisconsin

Event narrative

Heavy rain across the northern portion of Vernon County produced significant flash flooding. Over 200 people were evacuated in Coon Valley because of severe flooding along Coon Creek where U.S. Highway 14 and State Highway 162 were closed. All access into Coon Valley was cut off because of mudslides, washouts and closed roads. Numerous homes were severely damaged with basement walls blown out or had water several feet deep on the first floor. Much of Ontario was covered in flood waters from the Kickapoo River and Brush Creek with almost every business along Garden Street, State Highway 131 and the east end of Main Street sustaining damage. It was estimated that around 75% of the businesses in the entire village sustained some damage. The Ontario police squad car become submerged in flood waters and was destroyed. One boat rental business lost 40 canoes and 48 kayaks. Two campers along the Kickapoo River north of Rockton had to be rescued from flood waters that was neck high. Some residents were evacuated from Viola because of flooding along the Kickapoo River. A total of 350 water rescues were performed across the county. State Highway 131 was closed between Ontario and Rockton because of flood waters from the Kickapoo River where the asphalt was completely removed from the road bed in places or broken in large chunks and then moved up to eight feet from its original location. Numerous roads were closed because of the flooding or from mudslides. Flooding from Timber Coulee Creek washed out over 20 power poles north of Westby. The BNSF rail line was closed because of washouts between Stoddard and the La Crosse County line. The heavy rain and flooding caused two earthen flood control dams to fail and damaged four others. This prompted the evacuation and rescue of residents downstream from the dams, including the communities of Avalanche and Liberty. Wildcat Mountain State Park was closed because of the heavy rain as well.

Wider weather episode

A line of severe thunderstorms moved across western Wisconsin during the evening of August 27th. A brief tornado touched down and had an intermittent damage path between Tomah and Wyeville (Monroe County). The damage was limited to trees and power poles. These storms blew down trees and caused roof damage in Sparta (Monroe County), rolled a camper and damaged several signs near Tomah (Monroe County) and downed trees around Hixton (Jackson County) and in the Town of Cleveland (Jackson County). The storms then became oriented in an east to west line and dumped copious amounts of rain from southern La Crosse County and northern Vernon County east across the southern sections of Monroe, Juneau and Adams Counties. Numerous roads were closed because of flooding or mudslides, homes had to be evacuated with several water rescues were performed. Towns that were hit hard by the flooding included Coon Valley, Ontario (Vernon County), Elroy and Wonewoc (Juneau County). The eastbound Amtrak Empire Builder had to be halted near Tomah because of a washout on the rail line near Mauston (Juneau County). In Monroe and Vernon Counties, four earthen flood control dams failed and seven others sustained damage. Rainfall totals of 6 to 10 inches were common in this heavy rain band with the highest reported totals being 9.14 inches in Union Center (Juneau County) and 9.98 inches near Westby (Vernon County). The runoff later produced historic flooding on the Kickapoo River with several record flood crests established. Damages in Juneau County exceeded $22 million of which $6.5 million was from Elroy. The State of Wisconsin Governor declared a state of emergency for the entire state. A federal disaster declaration was made for La Crosse, Monroe, Juneau, Adams, Vernon, Crawford and Richland Counties.

View location on OpenStreetMap → (43.5134, -91.1978)

Source: NOAA Storm Events Database, event_id 776876. Narrative written by the NWS forecast office that issued the report.