USGS Streamgage 14378200
Illinois River near Agness, OR
Illinois River near Agness, OR is USGS streamgage 14378200 in Oregon, monitoring river discharge in hydrologic subbasin 17100311. It sits on the Illinois River, alongside 1 other gauge Rivermatics tracks on the same river. It drains a watershed of about 988 square miles. Discharge records at this site go back to 1960. Typical flow runs near 365.3 cfs in July and 3,835.7 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, alongside daily high and low water-temperature forecasts.
View live conditions & forecast →
Gauge details
- State
- Oregon
- Drainage area
- 988 sq mi
- Subbasin (HUC-8)
- 17100311
- Coordinates
- 42.54488, -124.05191
- USGS site number
- 14378200
- Records begin
- 1960-10-01 (66 years)
- Rivermatics forecast
- 14-day flow outlook + water temperature
14-day flow forecast
Based on observations through for Illinois River near Agness, OR. 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 |
|---|---|---|---|---|
| 184 | 189 | 196 | ||
| 185 | 196 | 219 | ||
| 185 | 200 | 238 | ||
| 178 | 192 | 219 | ||
| 171 | 184 | 203 | ||
| 166 | 179 | 196 | ||
| 162 | 175 | 192 | ||
| 158 | 173 | 191 | ||
| 155 | 170 | 187 | ||
| 153 | 168 | 185 | ||
| 152 | 167 | 184 | ||
| 150 | 165 | 183 | ||
| 147 | 164 | 182 | ||
| 146 | 163 | 181 |
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 66 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 | 1,307.1 | 5,009.7 | 29,880.6 | |
| February | 2,003.2 | 5,651 | 20,223.6 | |
| March | 2,157.1 | 4,977.7 | 17,018.4 | |
| April | 1,474.3 | 3,835.7 | 9,029.7 | |
| May | 1,093.1 | 1,788.7 | 5,642.3 | |
| June | 576.4 | 797.9 | 1,407.1 | |
| July | 262.6 | 365.3 | 506.6 | |
| August | 160.4 | 221.1 | 318.5 | |
| September | 149.1 | 186 | 466.3 | |
| October | 172.9 | 353.1 | 2,160.7 | |
| November | 419.8 | 2,348 | 14,982 | |
| December | 992.3 | 4,726.5 | 24,925.8 |
All values in cubic feet per second (cfs).
Common questions
- When does Illinois River near Agness, OR normally run highest?
- February, on the long-term record. The median daily flow that month is about 5,651 cfs, against 186 cfs in September, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Illinois River near Agness, OR?
- It depends on the month. In January, half of days historically fall near 5,009.7 cfs, with the middle 80% of days between 1,307.1 and 29,880.6 cfs. The month-by-month table on this page gives the full range.
- How long has Illinois River near Agness, OR been measured?
- Discharge records at USGS site 14378200 begin in 1960, about 66 years, covering roughly 678 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Illinois River near Agness, OR?
- 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. A companion model forecasts each day's water-temperature high and low. 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 Illinois River near Agness, OR?
- The gauge sits at 42.54488, -124.05191, in Oregon, in hydrologic subbasin 17100311, draining roughly 988 square miles.
- Can I use Illinois River near Agness, OR 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 Illinois River
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Illinois River in full.
- Illinois River near Kerby, OR 380 sq mi
- Illinois River near Agness, OR this page