USGS Streamgage 12389500
Thompson River near Thompson Falls, MT
Thompson River near Thompson Falls, MT is USGS streamgage 12389500 in Montana, monitoring river discharge in hydrologic subbasin 17010213. It drains a watershed of about 638 square miles. Discharge records at this site go back to 1911. Typical flow runs near 343 cfs in July and 640.6 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- Montana
- Drainage area
- 638 sq mi
- Gauge elevation
- 2,436 ft
- Subbasin (HUC-8)
- 17010213
- Coordinates
- 47.59186, -115.22954
- USGS site number
- 12389500
- Records begin
- 1911-03-01 (115 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 70 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 | 111.7 | 161.4 | 308.1 | |
| February | 117.7 | 175.3 | 406.4 | |
| March | 149.7 | 270.1 | 647.2 | |
| April | 299.2 | 640.6 | 1,388.3 | |
| May | 525.2 | 1,093.5 | 2,209.4 | |
| June | 348.4 | 798.7 | 1,731.3 | |
| July | 186.7 | 343 | 597.6 | |
| August | 132.7 | 215.5 | 308.3 | |
| September | 117.5 | 178.8 | 240.2 | |
| October | 116.5 | 167 | 223.7 | |
| November | 117.9 | 171.6 | 263.5 | |
| December | 108.4 | 163.6 | 301.3 |
All values in cubic feet per second (cfs).