USGS Streamgage 06126500
Musselshell River near Roundup, MT
Musselshell River near Roundup, MT is USGS streamgage 06126500 in Montana, monitoring river discharge in hydrologic subbasin 10040202. It sits on the Musselshell River, alongside 6 other gauges Rivermatics tracks on the same river. It drains a watershed of about 3,998 square miles. Discharge records at this site go back to 1946. Typical flow runs near 204.8 cfs in July and 81.1 cfs in April, with the higher of the two arriving in July. 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
- 3,998 sq mi
- Gauge elevation
- 3,193 ft
- Subbasin (HUC-8)
- 10040202
- Coordinates
- 46.42772, -108.5701
- USGS site number
- 06126500
- Records begin
- 1946-06-01 (80 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Musselshell River near Roundup, 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 |
|---|---|---|---|---|
| 45.1 | 57.8 | 73.2 | ||
| 41.2 | 58.9 | 84.5 | ||
| 37 | 59 | 91.9 | ||
| 33.2 | 57.7 | 93.1 | ||
| 28.9 | 54.5 | 88.7 | ||
| 24.7 | 51.5 | 85.6 | ||
| 20.6 | 48.6 | 82.1 | ||
| 20.3 | 47.7 | 81.9 | ||
| 19.6 | 46.7 | 81.9 | ||
| 17.4 | 43.9 | 79.5 | ||
| 15.4 | 42.6 | 80 | ||
| 14.9 | 41.9 | 79.1 | ||
| 14.7 | 42.9 | 81.6 | ||
| 12 | 39.9 | 79.7 |
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 79 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 | 10.9 | 40.8 | 150.2 | |
| February | 12.6 | 59.5 | 202.6 | |
| March | 21.3 | 97.3 | 410.6 | |
| April | 18.9 | 81.1 | 490.1 | |
| May | 49.6 | 204.8 | 1,075.9 | |
| June | 77 | 303.6 | 1,833 | |
| July | 61.9 | 204.8 | 705.5 | |
| August | 30.3 | 175.4 | 331.6 | |
| September | 12.4 | 101.7 | 255.6 | |
| October | 14.9 | 62.4 | 177.9 | |
| November | 14.3 | 57.4 | 177.9 | |
| December | 10.3 | 42.1 | 163.2 |
All values in cubic feet per second (cfs).
Common questions
- When does Musselshell River near Roundup, MT normally run highest?
- June, on the long-term record. The median daily flow that month is about 303.6 cfs, against 40.8 cfs in January, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Musselshell River near Roundup, MT?
- It depends on the month. In January, half of days historically fall near 40.8 cfs, with the middle 80% of days between 10.9 and 150.2 cfs. The month-by-month table on this page gives the full range.
- How long has Musselshell River near Roundup, MT been measured?
- Discharge records at USGS site 06126500 begin in 1946, about 80 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 Musselshell River near Roundup, 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 Musselshell River near Roundup, MT?
- The gauge sits at 46.42772, -108.5701, in Montana, in hydrologic subbasin 10040202, at an elevation of about 3,193 feet, draining roughly 3,998 square miles.
- Can I use Musselshell River near Roundup, 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.
Upstream and downstream on the Musselshell River
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Musselshell River in full.
- Musselshell River near Martinsdale, MT 537 sq mi
- Musselshell River at Harlowton, MT 1,108 sq mi
- Musselshell River ab Mud Creek near Shawmut, MT 1,518 sq mi
- Musselshell River ab Big Coulee Creek at Lavina, MT 2,691 sq mi
- Musselshell River near Roundup, MT this page
- Musselshell River at Musselshell, MT 4,534 sq mi
- Musselshell River at Mosby, MT 7,784 sq mi