Rivermatics

USGS Streamgage 12013500

Willapa River near Willapa, WA

Willapa River near Willapa, WA is USGS streamgage 12013500 in Washington, monitoring river discharge in hydrologic subbasin 17100106. It drains a watershed of about 130 square miles. Discharge records at this site go back to 1947. Typical flow runs near 64.7 cfs in July and 493.1 cfs in April, with the higher of the two arriving in April. Rivermatics issues a daily machine-learned flow outlook for this gauge, reaching 14 days ahead.

View live conditions & forecast →

Gauge details

State
Washington
Drainage area
130 sq mi
Gauge elevation
3 ft
Subbasin (HUC-8)
17100106
Coordinates
46.65093, -123.65266
USGS site number
12013500
Records begin
1947-08-26 (79 years)
Rivermatics forecast
14-day flow outlook

14-day flow forecast

Based on observations through for Willapa River near Willapa, WA. Each day carries a median estimate and the band the model expects the flow to fall within — not a single number to plan against. Forecasts are re-issued daily; see the live screen for the current outlook.

Forecast daily mean discharge in cubic feet per second, by date
Date Low p10 Expected p50 High p90 Range
26.7 28 29.3
26 28.6 34
28.5 36.1 59.2
28.7 37.4 61.7
26.8 32.8 46.5
25.1 29.8 38.8
23.5 27.6 34.7
22.2 25.9 31.9
21.8 25.4 31
21 24.6 29.8
20.5 24.1 29.1
19.7 23.2 28
19 22.5 27.4
18.5 22.1 26.9

All values in cubic feet per second (cfs). Estimates only — do not use them for navigation or for any safety, rescue, or emergency decision.

Typical flow by month

Long-term daily discharge percentiles from the USGS record (up to 78 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.

Historical monthly discharge percentiles in cubic feet per second
Month Low p10 Typical p50 High p90 Range
January 353.2 992.8 3,229.4
February 338.2 806.8 2,601.7
March 313.8 732.8 2,076.8
April 252.7 493.1 1,192.8
May 128.4 247 558.2
June 71.4 125.7 315.6
July 37.9 64.7 112.9
August 21.6 36 74.7
September 22.4 38.3 150.4
October 34.9 132.4 723.2
November 165 696.1 2,393.3
December 348.5 1,020.5 3,300.3

All values in cubic feet per second (cfs).

Common questions

When does Willapa River near Willapa, WA normally run highest?
December, on the long-term record. The median daily flow that month is about 1,020.5 cfs, against 36 cfs in August, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
What is a normal flow for Willapa River near Willapa, WA?
It depends on the month. In January, half of days historically fall near 992.8 cfs, with the middle 80% of days between 353.2 and 3,229.4 cfs. The month-by-month table on this page gives the full range.
How long has Willapa River near Willapa, WA been measured?
Discharge records at USGS site 12013500 begin in 1947, about 79 years, covering roughly 9,200 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
Is there a flow forecast for Willapa River near Willapa, WA?
Yes. Rivermatics trains a machine-learned model — a temporal-fusion transformer — on this basin's observed flows, weather, and snowpack, and issues a daily flow outlook reaching 14 days ahead: a median estimate inside a confidence band, not a single number to bet on. Every forecast is scored against days the model never trained on, and that track record is published on the live gauge screen. Open live conditions to see the current outlook.
Where is Willapa River near Willapa, WA?
The gauge sits at 46.65093, -123.65266, in Washington, in hydrologic subbasin 17100106, at an elevation of about 3 feet, draining roughly 130 square miles.
Can I use Willapa River near Willapa, WA data for flood or safety decisions?
No. Rivermatics provides estimates, not guarantees, and the readings and forecasts here may be delayed, inaccurate, or wrong. Do not use them for navigation or for any safety, rescue, or emergency decision. Check the National Weather Service and USGS directly, and use your own judgment.

Other gauges in this subbasin