USGS Streamgage 12148500
Tolt River near Carnation, WA
Tolt River near Carnation, WA is USGS streamgage 12148500 in Washington, monitoring river discharge in hydrologic subbasin 17110010. It drains a watershed of about 81 square miles. Discharge records at this site go back to 1928. Typical flow runs near 232.5 cfs in July and 580 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, alongside daily high and low water-temperature forecasts.
View live conditions & forecast →
Gauge details
- State
- Washington
- Drainage area
- 81 sq mi
- Gauge elevation
- 356 ft
- Subbasin (HUC-8)
- 17110010
- Coordinates
- 47.69566, -121.82401
- USGS site number
- 12148500
- Records begin
- 1928-09-01 (98 years)
- Rivermatics forecast
- 14-day flow outlook + water temperature
14-day flow forecast
Based on observations through for Tolt River near Carnation, WA. 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 | 107 | ||
| 101 | 104 | 107 | ||
| 111 | 140 | 239 | ||
| 113 | 145 | 241 | ||
| 108 | 126 | 170 | ||
| 104 | 114 | 137 | ||
| 101 | 109 | 128 | ||
| 98.7 | 106 | 121 | ||
| 97.3 | 104 | 118 | ||
| 96.3 | 103 | 118 | ||
| 95.4 | 102 | 114 | ||
| 94.3 | 101 | 112 | ||
| 93.7 | 101 | 112 | ||
| 93.1 | 100 | 112 |
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 98 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 | 305.2 | 645 | 1,755.2 | |
| February | 296.8 | 554.5 | 1,375.9 | |
| March | 311 | 526.3 | 1,085.5 | |
| April | 371.6 | 580 | 1,066.1 | |
| May | 335.3 | 597.2 | 1,067.5 | |
| June | 234.5 | 442.9 | 972.9 | |
| July | 149.5 | 232.5 | 471.7 | |
| August | 104.1 | 146.1 | 265 | |
| September | 95 | 151.8 | 463.2 | |
| October | 131.3 | 292.8 | 928 | |
| November | 248.6 | 586.5 | 1,526 | |
| December | 318.3 | 652 | 1,589.4 |
All values in cubic feet per second (cfs).
Common questions
- When does Tolt River near Carnation, WA normally run highest?
- December, on the long-term record. The median daily flow that month is about 652 cfs, against 146.1 cfs in August, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Tolt River near Carnation, WA?
- It depends on the month. In January, half of days historically fall near 645 cfs, with the middle 80% of days between 305.2 and 1,755.2 cfs. The month-by-month table on this page gives the full range.
- How long has Tolt River near Carnation, WA been measured?
- Discharge records at USGS site 12148500 begin in 1928, about 98 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 Tolt River near Carnation, WA?
- 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. A companion model forecasts each day's water-temperature high and low. 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 Tolt River near Carnation, WA?
- The gauge sits at 47.69566, -121.82401, in Washington, in hydrologic subbasin 17110010, at an elevation of about 356 feet, draining roughly 81 square miles.
- Can I use Tolt River near Carnation, WA 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.
Other gauges in this subbasin
- Snoqualmie River near Carnation, WA
- Snoqualmie River at Duvall, WA
- Middle Fork Snoqualmie River near Tanner, WA
- NF Snoqualmie River near Snoqualmie Falls, WA
- North Fork Snoqualmie River near North Bend, WA
- SF Snoqualmie River Ab Alice Creek near Garcia, WA
- SF Snoqualmie River at Edgewick, WA
- Boxley Creek near Cedar Falls, WA