USGS Streamgage 06191000
Gardner River near Mammoth, YNP
Gardner River near Mammoth, YNP is USGS streamgage 06191000 in Montana, monitoring river discharge in hydrologic subbasin 10070001. It drains a watershed of about 199 square miles. Discharge records at this site go back to 1938. Typical flow runs near 260 cfs in July and 126.3 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
- 199 sq mi
- Gauge elevation
- 5,632 ft
- Subbasin (HUC-8)
- 10070001
- Coordinates
- 44.99234, -110.69097
- USGS site number
- 06191000
- Records begin
- 1938-10-01 (88 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Gardner River near Mammoth, YNP. 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 |
|---|---|---|---|---|
| 101 | 104 | 108 | ||
| 99.8 | 104 | 108 | ||
| 98.2 | 103 | 107 | ||
| 97.1 | 102 | 107 | ||
| 95.7 | 101 | 107 | ||
| 94.5 | 101 | 107 | ||
| 93.4 | 100 | 107 | ||
| 92 | 99.5 | 107 | ||
| 90.9 | 98.8 | 107 | ||
| 90.3 | 98.6 | 107 | ||
| 89.7 | 98.3 | 108 | ||
| 89 | 97.9 | 108 | ||
| 88.4 | 97.5 | 107 | ||
| 87.7 | 97.1 | 107 |
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 88 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 | 80.7 | 95.3 | 112.7 | |
| February | 79.3 | 91.5 | 106 | |
| March | 80.9 | 92.1 | 108.8 | |
| April | 90.2 | 126.3 | 215.7 | |
| May | 245.3 | 447.4 | 856 | |
| June | 312.6 | 630 | 1,135.2 | |
| July | 149.4 | 260 | 456.3 | |
| August | 111.5 | 150 | 205.5 | |
| September | 102.1 | 129.6 | 165.7 | |
| October | 98.8 | 121.9 | 150.5 | |
| November | 89.8 | 109.5 | 134 | |
| December | 83.4 | 100.4 | 118.7 |
All values in cubic feet per second (cfs).
Common questions
- When does Gardner River near Mammoth, YNP normally run highest?
- June, on the long-term record. The median daily flow that month is about 630 cfs, against 91.5 cfs in February, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Gardner River near Mammoth, YNP?
- It depends on the month. In January, half of days historically fall near 95.3 cfs, with the middle 80% of days between 80.7 and 112.7 cfs. The month-by-month table on this page gives the full range.
- How long has Gardner River near Mammoth, YNP been measured?
- Discharge records at USGS site 06191000 begin in 1938, about 88 years, covering roughly 9,199 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Gardner River near Mammoth, YNP?
- 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 Gardner River near Mammoth, YNP?
- The gauge sits at 44.99234, -110.69097, in Montana, in hydrologic subbasin 10070001, at an elevation of about 5,632 feet, draining roughly 199 square miles.
- Can I use Gardner River near Mammoth, YNP 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.