Santa Margarita River at Ysidora, CA
River level and flood forecast · San Diego County
The river is 4.9 ft below flood stage (12.5 ft).
Forecast to rise to 7.8 ft Tue 1 AM, below the 12.5 ft flood stage.
Flow: 26 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Mon, Oct 12, 7:56 AM. Forecasts change as rain falls and as upstream water arrives.
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An email when the National Weather Service forecasts Santa Margarita River at Ysidora to flood, when it floods, and when it's over.
Flood stages
| Major flood stage | 16.29 ft |
| Moderate flood stage | 13.78 ft |
| Flood stage | 12.5 ft |
| Action stage | 10.85 ft |
| Record crest (February 14, 2019) | 15.07 ft |
What floods at each level
From the National Weather Service, highest first.
- 16.29 ftMajor flood, 37,000 cfs. Widespread inundation of Camp Pendleton with evacuations likely. Flood of Record Jan 16, 1993.
- 13.78 ftModerate flood stage, 17,000 cfs. Vandegrift Road is flooded for several miles downstream of the gage site. Stuart Mesa Road is flooded near the bridge.
- 12.5 ftMinor flood stage, 8,000 cfs. Vandegrift Road has begun to flood downstream of the gage. Stuart Mesa Road closures can be expected.
- 10.85 ft2,500 cfs. The river has reached monitor stage. Personnel begin regular patrols along the levee.
Highest crests on record
- 15.07 ft — February 14, 2019
- 14.6 ft — January 22, 2017
- 14.05 ft — January 23, 1943
- 12.7 ft — March 3, 1938
- 12.68 ft — January 10, 1995
Recent crests: 11.73 ft (January 16, 2023) · 15.07 ft (February 14, 2019) · 14.6 ft (January 22, 2017) · 12.41 ft (February 23, 1998) · 12.68 ft (January 10, 1995)
Up and down the river, and nearby
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (YDRC1); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.