Cowlitz River below Mayfield Dam, WA
River level and flood forecast · Lewis County
Normalas of Mon 9 PM
Forecast to hold near 3.7 ft through Mon, Oct 19, 5 PM.
Flow: 3,660 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Mon, Oct 12, 8:20 AM. Forecasts change as rain falls and as upstream water arrives.
What floods at each level
From the National Weather Service, highest first.
- 60000 ftthe Cowlitz River will cause severe near record flooding below Mayfield Dam downstream through Toledo. Deep and swift flood waters will inundate farmlands...roads...and some residential areas...especially near Toledo. Major damage due to erosion is likely. Flooding will occur all along the river including headwaters...tributaries...and other streams within and near the Cowlitz River Basin.
- 45000 ftthe Cowlitz River will cause major flooding from Mayfield Dam downstream through Toledo. Deep and swift flood waters will inundate farmlands...roads...and some residential areas...especially near Toledo. Some damage due to erosion is possible. Flooding will occur all along the river including headwaters...tributaries...and other streams within and near the Cowlitz River Basin.
- 35000 ftthe Cowlitz River will flood the reach from Mayfield Dam downstream through Toledo. Swift flood waters will inundate some farmlands and several roads...especially near Toledo.
- 25000 ftthe Cowlitz River will flood the reach from Mayfield Dam downstream through Toledo. Flood waters will inundate some farmlands and several roads...mainly near Toledo.
Highest crests on record
- 26.19 ft — November 28, 1995
- 25.26 ft — December 4, 1975
- 24.75 ft — December 13, 1946
- 24.36 ft — January 30, 1965
- 23.71 ft — November 24, 1959
Recent crests: 19.03 ft (December 13, 2025) · 20.59 ft (January 7, 2009) · 19.34 ft (November 9, 2006) · 17.83 ft (January 4, 1997) · 26.19 ft (November 28, 1995)
Up and down the river, and nearby
- UpstreamCowlitz River at Randle, WA
- DownstreamCowlitz River at Castle Rock, WA
- South Fork Newaukum River near Onalaska, WA
- Tilton River near Cinebar, WA
- N Fk Toutle River below Sediment Retention Structure near Toutle, WA
- North Fork Newaukum River near Forest, WA
- Toutle River at Tower Road near Silver Lake, WA
- Newaukum River near Chehalis, WA
- Skookumchuck River near Vail, WA
- Skookumchuck River Below Bloody Run, WA
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (MAYW1); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.