San Marcos, CA All-Time Weather Extremes
The most extreme temperature, precipitation, and snowfall ever recorded in San Marcos, from NOAA daily weather observations.
| Temperature | ||
|---|---|---|
| Record High | 107.9°F (42°C) | June 30, 1985 |
| Record Low | 23°F (-5°C) | December 18, 2007 |
| Lowest High | 48.9°F (9°C) | December 10, 1972 |
| Highest Low | 80°F (27°C) | July 2, 1985 |
| Highest Mean | 91°F (33°C) | July 2, 1985 |
| Lowest Mean | 40.0°F (4°C) | December 25, 1987 |
| Precipitation | ||
| Max in One Calendar Day | 3.26" (82.8 mm) | February 28, 1991 |
| Max in One Month | 12.29" (312.1 mm) | January 1993 |
| Least in One Month | 0.00" (0.0 mm) | September 1979 |
| Max in One Year | 28.37" (720.6 mm) | 1978 |
| Least in One Year | 3.81" (96.7 mm) | 1989 |
| Snowfall | ||
| Max in One Calendar Day | 16.0" (40.6 cm) | February 26, 2004 |
| Max in One Month | 16.0" (40.6 cm) | February 2004 |
| Max in One Season | 16.0" (40.6 cm) | 2003-04 |
| Max in One Year | 16.0" (40.6 cm) | 2004 |
| Earliest Snow | 1.0" (2.5 cm) | January 25, 1979 |
| Earliest Measurable Snow | 1.0" (2.5 cm) | January 25, 1979 |
| Latest Snow | 16.0" (40.6 cm) | February 26, 2004 |
| Latest Measurable Snow | 16.0" (40.6 cm) | February 26, 2004 |
| Period of Record | ||
| Temperature | January 1, 1970 – May 31, 2026 | |
| Precipitation | January 1, 1970 – May 31, 2026 | |
| Snowfall | January 1, 1970 – December 31, 2010 | |
Note: Records compiled from NOAA GHCN-Daily observations at VISTA (7 mi from San Marcos, CA). Quality-flagged readings are excluded. Monthly and annual totals require substantially complete reporting for “least” records.
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Frequently Asked Questions
What is the hottest temperature ever recorded in San Marcos, CA?
The all-time record high in San Marcos, CA is 107.9°F (42°C), set on June 30, 1985.
What is the coldest temperature ever recorded in San Marcos, CA?
The all-time record low in San Marcos, CA is 23°F (-5°C), set on December 18, 2007.
What is the most rain San Marcos, CA has ever had in one day?
The most precipitation recorded in one calendar day near San Marcos, CA is 3.26 inches, on February 28, 1991.
What is the biggest snowfall ever recorded in San Marcos, CA?
The most snow recorded in one calendar day near San Marcos, CA is 16.0 inches, on February 26, 2004.
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