USGS Streamgage 13023000
Greys River above Reservoir, near Alpine, WY
Greys River above Reservoir, near Alpine, WY is USGS streamgage 13023000 in Wyoming, monitoring river discharge in hydrologic subbasin 17040103. It drains a watershed of about 448 square miles. Discharge records at this site go back to 1917. Typical flow runs near 786.1 cfs in July and 578.8 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
- Wyoming
- Drainage area
- 448 sq mi
- Subbasin (HUC-8)
- 17040103
- Coordinates
- 43.14306, -110.97694
- USGS site number
- 13023000
- Records begin
- 1917-07-06 (109 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Greys River above Reservoir, near Alpine, WY. 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 |
|---|---|---|---|---|
| 250 | 259 | 268 | ||
| 246 | 256 | 267 | ||
| 241 | 252 | 263 | ||
| 237 | 249 | 260 | ||
| 234 | 245 | 257 | ||
| 231 | 243 | 255 | ||
| 230 | 243 | 256 | ||
| 227 | 241 | 253 | ||
| 225 | 239 | 252 | ||
| 222 | 237 | 251 | ||
| 219 | 234 | 249 | ||
| 217 | 233 | 248 | ||
| 214 | 230 | 246 | ||
| 212 | 228 | 245 |
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 89 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 | 150.7 | 205.6 | 277.4 | |
| February | 151.9 | 198.5 | 252.7 | |
| March | 169.8 | 214.1 | 333.5 | |
| April | 297.2 | 578.8 | 1,167.5 | |
| May | 930.7 | 1,643.2 | 2,824.5 | |
| June | 967.1 | 1,805 | 3,196.3 | |
| July | 451.4 | 786.1 | 1,503.7 | |
| August | 308.6 | 451.4 | 681.2 | |
| September | 257.2 | 352.3 | 504.7 | |
| October | 228.3 | 306.3 | 422.7 | |
| November | 195 | 261.4 | 356.2 | |
| December | 162.8 | 224.8 | 302 |
All values in cubic feet per second (cfs).
Common questions
- When does Greys River above Reservoir, near Alpine, WY normally run highest?
- June, on the long-term record. The median daily flow that month is about 1,805 cfs, against 198.5 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 Greys River above Reservoir, near Alpine, WY?
- It depends on the month. In January, half of days historically fall near 205.6 cfs, with the middle 80% of days between 150.7 and 277.4 cfs. The month-by-month table on this page gives the full range.
- How long has Greys River above Reservoir, near Alpine, WY been measured?
- Discharge records at USGS site 13023000 begin in 1917, about 109 years, covering roughly 9,201 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Greys River above Reservoir, near Alpine, WY?
- 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 Greys River above Reservoir, near Alpine, WY?
- The gauge sits at 43.14306, -110.97694, in Wyoming, in hydrologic subbasin 17040103, draining roughly 448 square miles.
- Can I use Greys River above Reservoir, near Alpine, WY 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.