USGS Streamgage 13305000
Lemhi River near Lemhi, ID
Lemhi River near Lemhi, ID is USGS streamgage 13305000 in Idaho, monitoring river discharge in hydrologic subbasin 17060204. It sits on the Lemhi River, alongside 2 other gauges Rivermatics tracks on the same river. It drains a watershed of about 897 square miles. Discharge records at this site go back to 1938. Typical flow runs near 215.5 cfs in July and 251.7 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.
View live conditions & forecast →
Gauge details
- State
- Idaho
- Drainage area
- 897 sq mi
- Subbasin (HUC-8)
- 17060204
- Coordinates
- 44.94, -113.63917
- USGS site number
- 13305000
- Records begin
- 1938-12-01 (88 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Lemhi River near Lemhi, ID. 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 |
|---|---|---|---|---|
| 103 | 108 | 111 | ||
| 96.9 | 105 | 112 | ||
| 94.5 | 105 | 114 | ||
| 90.2 | 103 | 113 | ||
| 89.2 | 102 | 116 | ||
| 90.2 | 105 | 122 | ||
| 90.8 | 106 | 125 | ||
| 90.7 | 108 | 129 | ||
| 89.3 | 107 | 129 | ||
| 89 | 108 | 133 | ||
| 87.5 | 107 | 136 | ||
| 86.7 | 107 | 138 | ||
| 85.9 | 106 | 138 | ||
| 85.2 | 106 | 137 |
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 86 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 | 164.9 | 216 | 284.9 | |
| February | 172.9 | 224.7 | 290.1 | |
| March | 185.9 | 250.2 | 329.7 | |
| April | 146.5 | 251.7 | 346 | |
| May | 122.1 | 260.2 | 556.6 | |
| June | 182.6 | 437.2 | 967.2 | |
| July | 97.5 | 215.5 | 477.1 | |
| August | 76.8 | 117.8 | 218.5 | |
| September | 81.5 | 131.8 | 241.5 | |
| October | 140.3 | 234.6 | 337.6 | |
| November | 195.9 | 262 | 345 | |
| December | 168.2 | 219.7 | 284.9 |
All values in cubic feet per second (cfs).
Common questions
- When does Lemhi River near Lemhi, ID normally run highest?
- June, on the long-term record. The median daily flow that month is about 437.2 cfs, against 117.8 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 Lemhi River near Lemhi, ID?
- It depends on the month. In January, half of days historically fall near 216 cfs, with the middle 80% of days between 164.9 and 284.9 cfs. The month-by-month table on this page gives the full range.
- How long has Lemhi River near Lemhi, ID been measured?
- Discharge records at USGS site 13305000 begin in 1938, about 88 years, covering roughly 9,188 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Lemhi River near Lemhi, ID?
- 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 Lemhi River near Lemhi, ID?
- The gauge sits at 44.94, -113.63917, in Idaho, in hydrologic subbasin 17060204, draining roughly 897 square miles.
- Can I use Lemhi River near Lemhi, ID 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 Lemhi River
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Lemhi River in full.
- Lemhi River near Lemhi, ID this page
- Lemhi River below L5 Diversion near Salmon, ID 1,216 sq mi
- Lemhi River near McFarland, ID