USGS Streamgage 09384600
Lyman Lake near St. Johns, AZ
Lyman Lake near St. Johns, AZ is USGS streamgage 09384600 in Arizona, monitoring river discharge in hydrologic subbasin 15020001. It drains a watershed of about 790 square miles. Discharge records at this site go back to 1984. Typical flow runs near 0 cfs in July and 160.5 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- Arizona
- Drainage area
- 790 sq mi
- Gauge elevation
- 5,980 ft
- Subbasin (HUC-8)
- 15020001
- Coordinates
- 34.37448, -109.38482
- USGS site number
- 09384600
- Records begin
- 1984-10-01 (42 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 1 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 | — | |
| February | — | 0 | — | |
| March | — | 82.8 | — | |
| April | — | 160.5 | — | |
| May | — | 55 | — | |
| June | — | 0 | — | |
| July | — | 0 | — | |
| August | — | 0 | — | |
| September | — | 0 | — | |
| October | — | 0 | — | |
| November | — | 0 | — | |
| December | — | 0 | — |
All values in cubic feet per second (cfs).
Common questions
- When does Lyman Lake near St. Johns, AZ normally run highest?
- April, on the long-term record. The median daily flow that month is about 160.5 cfs, against 0 cfs in January, the lowest month. These are historical normals for the date, not a forecast and not today's reading.
- How long has Lyman Lake near St. Johns, AZ been measured?
- Discharge records at USGS site 09384600 begin in 1984, about 42 years, covering roughly 7 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Lyman Lake near St. Johns, AZ?
- The gauge sits at 34.37448, -109.38482, in Arizona, in hydrologic subbasin 15020001, at an elevation of about 5,980 feet, draining roughly 790 square miles.
- Can I use Lyman Lake 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.