USGS Streamgage 12035400
Wynoochee River near Grisdale, WA
Wynoochee River near Grisdale, WA is USGS streamgage 12035400 in Washington, monitoring river discharge in hydrologic subbasin 17100104. It sits on the Wynoochee River, alongside 2 other gauges Rivermatics tracks on the same river. It drains a watershed of about 41 square miles. Discharge records at this site go back to 1965. Typical flow runs near 231.5 cfs in July and 233.5 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
- 41 sq mi
- Gauge elevation
- 633 ft
- Subbasin (HUC-8)
- 17100104
- Coordinates
- 47.38034, -123.60986
- USGS site number
- 12035400
- Records begin
- 1965-10-01 (61 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Wynoochee River near Grisdale, 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.
| Date | Low p10 | Expected p50 | High p90 | Range |
|---|---|---|---|---|
| 192 | 196 | 200 | ||
| 192 | 198 | 227 | ||
| 192 | 201 | 263 | ||
| 191 | 198 | 250 | ||
| 190 | 198 | 246 | ||
| 189 | 197 | 246 | ||
| 189 | 197 | 264 | ||
| 188 | 197 | 280 | ||
| 188 | 199 | 287 | ||
| 188 | 200 | 292 | ||
| 187 | 199 | 292 | ||
| 187 | 200 | 302 | ||
| 186 | 200 | 304 | ||
| 186 | 201 | 303 |
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 61 years of data), averaged within each month. These describe the historical normal range — they are not a forecast and not today's reading.
| Month | Low p10 | Typical p50 | High p90 | Range |
|---|---|---|---|---|
| January | 257.4 | 689.4 | 1,793.9 | |
| February | 232.7 | 482.4 | 1,462.4 | |
| March | 209.3 | 349.5 | 1,206.6 | |
| April | 202.2 | 233.5 | 633.9 | |
| May | 207 | 243.5 | 618.5 | |
| June | 208 | 263.4 | 529.6 | |
| July | 179.2 | 231.5 | 359.4 | |
| August | 159.7 | 218.5 | 288.7 | |
| September | 179.4 | 237.6 | 542.8 | |
| October | 189.8 | 299.3 | 1,059.6 | |
| November | 226.1 | 617.8 | 1,779.7 | |
| December | 258.3 | 698.2 | 1,997.1 |
All values in cubic feet per second (cfs).
Common questions
- When does Wynoochee River near Grisdale, WA normally run highest?
- December, on the long-term record. The median daily flow that month is about 698.2 cfs, against 218.5 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 Wynoochee River near Grisdale, WA?
- It depends on the month. In January, half of days historically fall near 689.4 cfs, with the middle 80% of days between 257.4 and 1,793.9 cfs. The month-by-month table on this page gives the full range.
- How long has Wynoochee River near Grisdale, WA been measured?
- Discharge records at USGS site 12035400 begin in 1965, about 61 years, covering roughly 9,183 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Wynoochee River near Grisdale, 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 Wynoochee River near Grisdale, WA?
- The gauge sits at 47.38034, -123.60986, in Washington, in hydrologic subbasin 17100104, at an elevation of about 633 feet, draining roughly 41 square miles.
- Can I use Wynoochee River near Grisdale, 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.
Upstream and downstream on the Wynoochee River
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Wynoochee River in full.
- Wynoochee River near Grisdale, WA this page
- Wynoochee River above Save Creek near Aberdeen, WA 74 sq mi
- Wynoochee River above Black Creek near Montesano, WA 155 sq mi