USGS Streamgage 11025500
Santa Ysabel C near Ramona, CA
Santa Ysabel C near Ramona, CA is USGS streamgage 11025500 in California, monitoring river discharge in hydrologic subbasin 18070304. It drains a watershed of about 112 square miles. Discharge records at this site go back to 1912. Typical flow runs near 0 cfs in July and 2.2 cfs in April, with the higher of the two arriving in April.
Gauge details
- State
- California
- Drainage area
- 112 sq mi
- Gauge elevation
- 850 ft
- Subbasin (HUC-8)
- 18070304
- Coordinates
- 33.10699, -116.86614
- USGS site number
- 11025500
- Records begin
- 1912-02-01 (114 years)
Typical flow by month
Long-term daily discharge percentiles from the USGS record (up to 72 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 | 0.4 | 19.7 | |
| February | 0 | 1.8 | 49.8 | |
| March | 0 | 2.9 | 73.9 | |
| April | 0 | 2.2 | 47.2 | |
| May | 0 | 0.6 | 18.5 | |
| June | 0 | 0 | 8.3 | |
| July | 0 | 0 | 2.4 | |
| August | 0 | 0 | 1 | |
| September | 0 | 0 | 0.6 | |
| October | 0 | 0 | 0.9 | |
| November | 0 | 0 | 2.2 | |
| December | 0 | 0 | 5.4 |
All values in cubic feet per second (cfs).
Common questions
- When does Santa Ysabel C near Ramona, CA normally run highest?
- March, on the long-term record. The median daily flow that month is about 2.9 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 Santa Ysabel C near Ramona, CA?
- It depends on the month. In January, half of days historically fall near 0.4 cfs, with the middle 80% of days between 0 and 19.7 cfs. The month-by-month table on this page gives the full range.
- How long has Santa Ysabel C near Ramona, CA been measured?
- Discharge records at USGS site 11025500 begin in 1912, about 114 years, covering roughly 9,126 days of published daily values. The long record is what makes the monthly percentiles on this page meaningful.
- Where is Santa Ysabel C near Ramona, CA?
- The gauge sits at 33.10699, -116.86614, in California, in hydrologic subbasin 18070304, at an elevation of about 850 feet, draining roughly 112 square miles.
- Can I use Santa Ysabel C near Ramona, CA 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.