Rivers in Washington

Chehalis River at Porter

Grays Harbor County, WashingtonNWS CRPW1USGS 12031000Seattle office

Below flood stage
30.53ftStage

Observed Wed, Sep 23, 12:45 PM PDT

Flood stage
48.00 ft
Forecast crest
30.75 ftSat, Sep 26, 5:00 PM PDT
Record crest
53.17 ft2007

Open the live map with the river flood outlook

Flood stages and impacts

CategoryStage
Major flood52.00 ft
Moderate flood50.00 ft
Minor flood48.00 ft
Action45.50 ft
  1. 52.00 ftthe Chehalis River in Grays Harbor will cause major near record flooding from Oakville downstream to Grays Harbor. Deep and swift flood waters will inundate numerous farms and roads...including SR 12. High tidal levels at Aberdeen will worsen flooding along the lower reaches. Flooding will occur all along the river including headwaters...tributaries...and other streams within and near the Chehalis River Basin.
  2. 50.00 ftfeet...the Chehalis River in Grays Harbor will flood numerous farms and roads including SR 12. High tidal levels at Aberdeen will worsen flooding along the lower reaches.
  3. 49.00 ftthe Chehalis River in Grays Harbor will flood pasture lands and many roads...including SR 12 between Oakville and Rochester. High tidal levels at Aberdeen will worsen flooding along the lower reaches.
  4. 48.00 ftthe Chehalis River in Grays Harbor will flood low pasture lands and some roads. High tidal levels at Aberdeen will worsen flooding along the lower reaches.
  5. 46.00 ftthe Chehalis River in Grays Harbor County will locally spill over its banks with shallow water on several roads.

Flood outlook

Chance of flooding, September to November

CategoryChance
Minor flooding15%
Moderate floodingUnder 5%
Major floodingUnder 5%

The three-month chances are the River Forecast Centers’ long-range flood outlook, issued September 23, 2026.

Crest history

177 crests on NOAA’s list since 1946.

#DateStage
1December 5, 200753.17 ft
2January 8, 202252.01 ft
3December 12, 202549.64 ft
4January 15, 202149.18 ft
5January 9, 202048.99 ft
6March 3, 202248.79 ft
7December 23, 201948.58 ft
8December 8, 202348.54 ft
9January 13, 202248.36 ft
10November 14, 202148.15 ft
11December 21, 202548.14 ft
12February 24, 202147.65 ft
13December 5, 200726.06 ft
14February 9, 199625.22 ft
15January 9, 200924.65 ft
16January 11, 199024.52 ft
17January 22, 197223.88 ft
18January 27, 197123.50 ft
19January 2, 199723.43 ft
20December 5, 197523.36 ft
21November 25, 198623.36 ft
22November 26, 199023.17 ft
23February 12, 199022.87 ft
24April 6, 199122.84 ft
25December 11, 201522.73 ft

Most recent crests

  • December 21, 2025: 48.14 ft
  • December 12, 2025: 49.64 ft
  • December 8, 2023: 48.54 ft
  • March 3, 2022: 48.79 ft
  • January 13, 2022: 48.36 ft
  • January 8, 2022: 52.01 ft
  • November 14, 2021: 48.15 ft
  • February 24, 2021: 47.65 ft
  • January 15, 2021: 49.18 ft
  • January 9, 2020: 48.99 ft

Nearby

Upstream, downstream and the gauges around this one.

What this means

Forecasts by the Northwest River Forecast Center. Forecasts are issued routinely year-round. 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.

Sources

Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.