Web Portal Changes:

• Attention: Technicians are currently working to bring Precipitation datasets back to full capability after the April 16 outage.
• NWPS - water.noaa.gov - Officially operational on Wednesday, March 27th, 8-9am EDT
• AHPS - water.weather.gov- Scheduled operations ends on Tuesday, May 28th, 2024 - the pages will automatically redirect to water.noaa.gov until May 28, 2025.
• Other Important URL changes - Service Change Notice 24-29 

Please visit https://www.weather.gov/owp/operations for more information.

Weather Forecast Office Seattle, WA

Northwest River Forecast Center

Hydrograph

River at a Glance

Download

Probability Information Weekly Chance of Exceeding Levels Not Available Chance of Exceeding Levels During Entire Period Not Available Short-term Probabilistic Guidance (Experimental) Not Available

Auto Refresh: OFF

Printable Image About this graph Tabular Data (UTC) Tabular Data (PDT) Datum: Not Available Metadata

NOTE: River forecasts for this location take into account past and future precipitation. The stages/flows that will occur may be different if future rainfall is different than forecast. Reliability of the Forecast: Based on current and forecast river, weather and reservoir conditions NOTE: Forecasts for the Cowlitz River below Mayfield Dam are issued routinely year-round.

Default Hydrograph Scale to Flood Categories   Return to Area Map

Upstream Gauge

Downstream Gauge

Flood Categories (in KCFS) Major Flood Flow: 45 Moderate Flood Flow: 35 Flood Flow: 25 Action Flow: 17 Low Stage (in feet): -9999 Historic Crests (1) 68,400 cfs on 11/28/1995 (2) 67,000 cfs on 12/13/1946 (3) 64,700 cfs on 12/04/1975 (4) 64,700 cfs on 01/30/1965 (5) 60,800 cfs on 11/24/1959 Show More Historic Crests (P): Preliminary values subject to further review. Recent Crests (1) 34,800 cfs on 01/07/2009 (2) 29,224 cfs on 11/09/2006 (3) 25,000 cfs on 01/04/1997 (4) 68,400 cfs on 11/28/1995 (5) 27,000 cfs on 02/19/1995 Show More Recent Crests (P): Preliminary values subject to further review. Low Water Records Currently none available.

Zoom Level:16 Legend FEMA Layer Gauge Location Disclaimer Latitude/Longitude Disclaimer: The gauge location shown in the above map is the approximate location based on the latitude/longitude coordinates provided to the NWS by the gauge owner.

Flood Impacts & Photos

If you notice any errors in the below information, please contact our Webmaster
60000	the 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	the 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	the 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	the Cowlitz River will flood the reach from Mayfield Dam downstream through Toledo. Flood waters will inundate some farmlands and several roads...mainly near Toledo.

About This Location

Latitude: 46.510556° N, Longitude: 122.615000° W, Horizontal Datum: NAD83/WGS84 River Stage Reference Frame Gauge Height Flood Stage Uses NWS flow Not Available Not Available Interpreting hydrographs and NWS watch, warnings, and forecasts, and inundation maps Vertical Datum Elevation (gauge height = 0) Elevation (gauge height = flood stage) Elevation information source NAVD88 Not Available Not Available Survey grade GPS equipment, FEMA flood plain maps, newer USGS topographic maps NGVD 29 226.6 Not Available Older USGS topographic maps, NGVD29 benchmarks MSL Not Available Not Available Older USGS topographic maps, MSL benchmarks Other Not Available Not Available   Current/Historical Observations: U.S. Geological Survey (USGS) Data and Site Info for Mayfield Dam

Resources

Hydrologic Resources Text Products Past Precipitation Forecast Precipitation River Forecast Centers River Stage Summary USGS Streamflow Data USACE real time/archived data query

Additional Resources Area Hydrographs NWS Precipitation and River Forecasting AHPS Iframes for Developers Mobile iNWS for emergency management Inundation Mapping Locations Snow Information Flood Smart/National Flood Insurance Program

Collaborative Agencies The National Weather Service prepares its forecasts and other services in collaboration with agencies like the US Geological Survey, US Bureau of Reclamation, US Army Corps of Engineers, Natural Resource Conservation Service, National Park Service, ALERT Users Group, Bureau of Indian Affairs, and many state and local emergency managers across the country. For details, please click here. NWS Information National Weather Service Seattle Weather Forecast Office 7600 Sandpoint Way NE Seattle, WA 98115-6349 (206) 526-6087 Ask Questions/Webmaster Page last modified: 2-Nov-2020 7:27 PM Disclaimer Credits Glossary Privacy Policy About Us Career Opportunities