USGS Streamgage 09386030
Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ
Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ is USGS streamgage 09386030 in Arizona, monitoring river discharge in hydrologic subbasin 15020002. It sits on the Little Colorado Rvr, alongside 1 other gauge Rivermatics tracks on the same river. It drains a watershed of about 1,007 square miles. Discharge records at this site go back to 1975. Typical flow runs near 0.1 cfs in July and 0.3 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.
View live conditions & forecast →
Gauge details
- State
- Arizona
- Drainage area
- 1,007 sq mi
- Gauge elevation
- 5,570 ft
- Subbasin (HUC-8)
- 15020002
- Coordinates
- 34.58332, -109.40669
- USGS site number
- 09386030
- Records begin
- 1975-10-01 (51 years)
- Rivermatics forecast
- 14-day flow outlook
14-day flow forecast
Based on observations through for Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ. 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 |
|---|---|---|---|---|
| 0 | 0 | 2.2 | ||
| 0 | 0 | 0.2 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0 | ||
| 0 | 0 | 0 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0.1 | ||
| 0 | 0 | 0 |
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 51 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 | 0 | 1.3 | 12.1 | |
| February | 0 | 1 | 12.7 | |
| March | 0 | 0.7 | 12.7 | |
| April | 0 | 0.3 | 20.9 | |
| May | 0 | 0.1 | 18.9 | |
| June | 0 | 0 | 2.7 | |
| July | 0 | 0.1 | 7.1 | |
| August | 0 | 0.3 | 11.4 | |
| September | 0 | 0.2 | 7.1 | |
| October | 0 | 1.4 | 8.8 | |
| November | 0 | 1.7 | 10.8 | |
| December | 0 | 0.9 | 12.4 |
All values in cubic feet per second (cfs).
Common questions
- When does Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ normally run highest?
- November, on the long-term record. The median daily flow that month is about 1.7 cfs, against 0 cfs in June, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- What is a normal flow for Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ?
- It depends on the month. In January, half of days historically fall near 1.3 cfs, with the middle 80% of days between 0 and 12.1 cfs. The month-by-month table on this page gives the full range.
- How long has Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ been measured?
- Discharge records at USGS site 09386030 begin in 1975, about 51 years, covering roughly 9,129 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Is there a flow forecast for Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ?
- 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 Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ?
- The gauge sits at 34.58332, -109.40669, in Arizona, in hydrologic subbasin 15020002, at an elevation of about 5,570 feet, draining roughly 1,007 square miles.
- Can I use Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ 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 Little Colorado Rvr
Every gauge Rivermatics tracks on this river, ordered by drainage area — upstream first. See the Little Colorado Rvr in full.
- Little Colorado Rvr above Zion Reservoir. near St. Johns, AZ this page
- Little Colorado Rvr below Zion Reservoir. near St Johns, AZ 1,171 sq mi