USGS Streamgage 12301250
Tobacco River at Eureka, MT
Tobacco River at Eureka, MT is USGS streamgage 12301250 in Montana, monitoring river discharge in hydrologic subbasin 17010101. It drains a watershed of about 396 square miles. Discharge records at this site go back to 2015. Typical flow runs near 168.2 cfs in July and 297.9 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
- Montana
- Drainage area
- 396 sq mi
- Gauge elevation
- 2,563 ft
- Subbasin (HUC-8)
- 17010101
- Coordinates
- 48.87795, -115.05446
- USGS site number
- 12301250
- Records begin
- 2015-11-10 (11 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Tobacco River at Eureka, MT. 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 |
|---|---|---|---|---|
| 117 | 128 | 143 | ||
| 111 | 124 | 142 | ||
| 115 | 134 | 171 | ||
| 116 | 142 | 189 | ||
| 113 | 135 | 174 | ||
| 109 | 129 | 161 | ||
| 104 | 122 | 150 | ||
| 99.5 | 117 | 142 | ||
| 95.7 | 112 | 134 | ||
| 92.9 | 108 | 128 | ||
| 90.1 | 105 | 123 | ||
| 87.9 | 102 | 120 | ||
| 86.2 | 101 | 119 | ||
| 83.9 | 98.1 | 115 |
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 11 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 | 53.3 | 85.5 | 128.5 | |
| February | 50.7 | 88.3 | 158.8 | |
| March | 57.3 | 118.8 | 402.8 | |
| April | 153 | 297.9 | 782 | |
| May | 380 | 652.1 | 1,410.3 | |
| June | 204.2 | 513.8 | 1,490.3 | |
| July | 75.9 | 168.2 | 518.1 | |
| August | 41.5 | 83.3 | 136.9 | |
| September | 47.9 | 79.7 | 104.8 | |
| October | 64.3 | 84.3 | 206.4 | |
| November | 71.4 | 95.9 | 305 | |
| December | 63.1 | 90.5 | 300.9 |
All values in cubic feet per second (cfs).
Common questions
- When does Tobacco River at Eureka, MT normally run highest?
- May, on the long-term record. The median daily flow that month is about 652.1 cfs, against 79.7 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 Tobacco River at Eureka, MT?
- It depends on the month. In January, half of days historically fall near 85.5 cfs, with the middle 80% of days between 53.3 and 128.5 cfs. The month-by-month table on this page gives the full range.
- How long has Tobacco River at Eureka, MT been measured?
- Discharge records at USGS site 12301250 begin in 2015, about 11 years, covering roughly 3,921 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Tobacco River at Eureka, MT?
- 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 Tobacco River at Eureka, MT?
- The gauge sits at 48.87795, -115.05446, in Montana, in hydrologic subbasin 17010101, at an elevation of about 2,563 feet, draining roughly 396 square miles.
- Can I use Tobacco River at Eureka, MT 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.