Frost dates for 92078San Marcos, CA
Frost occurs in about 39% of years near San Marcos, based on NOAA 1991-2020 records for the Escondido #2, CA station.
Frost occurs in about 39% of years. Frost-tender plants can usually grow year-round, but cover them if a rare cold snap is forecast.
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Dec 29 · Jan 31 · Mar 1 | Nov 27 · Dec 18 · Jan 19 | 324 days | 94% |
| Frost / freeze (32°F) | Dec 14 · Jan 2 · Feb 4 | Dec 8 · Dec 30 · Jan 29 | 365 days | 39% |
| Hard freeze (28°F) | — | — | 365 days | 3% |
Where these dates come from
ZIP code 92078 is matched to the NOAA station Escondido #2, CA, 8.8 km away, at 600 ft elevation (115 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Escondido #2, CA (used) | 600 ft | Jan 2 | Dec 30 |
| Carlsbad Palomar Ap, CA | 328 ft | — | — |
| Vista, CA | 430 ft | Jan 30 | Jan 7 |
| Rancho Bernardo, CA | 690 ft | Jan 5 | Jan 2 |
Frost dates near San Marcos
- San Marcos, CA 92069 · last Jan 2, first Dec 30
- Vista, CA 92081 · last Jan 30, first Jan 7
- Escondido, CA 92029 · last Jan 2, first Dec 30
- Carlsbad, CA 92009 · last —, first —
- Encinitas, CA 92024 · last —, first —
- Oceanside, CA 92056 · last Jan 30, first Jan 7
- Rancho Santa Fe, CA 92067 · last —, first —
- Cardiff By The Sea, CA 92007 · last —, first —
Frequently asked questions
- When is the last frost in San Marcos, CA?
- Frost occurs in about 39% of years at the nearest NOAA station (Escondido #2, CA), so there is no reliable average last frost date.
- When is the first frost in San Marcos, CA?
- Frost occurs in about 39% of years at the nearest NOAA station.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.