Frost dates for 93443Morro Bay, CA
Frost occurs in about 15% of years near Morro Bay, based on NOAA 1991-2020 records for the Morro Bay Fire Dept, CA station.
Frost occurs in about 15% 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 18 · Jan 21 · Feb 21 | Dec 8 · Dec 31 · Feb 4 | 356 days | 62% |
| Frost / freeze (32°F) | Dec 30 · Jan 19 · Feb 9 | Dec 25 · Jan 14 · Feb 8 | 365 days | 15% |
| Hard freeze (28°F) | — | — | 365 days | 3% |
Where these dates come from
ZIP code 93443 is matched to the NOAA station Morro Bay Fire Dept, CA, 0.5 km away, at 118 ft elevation (62 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Morro Bay Fire Dept, CA (used) | 118 ft | Jan 19 | Jan 14 |
| San Luis Obispo Poly, CA | 308 ft | Jan 16 | Dec 25 |
| San Luis Obispo Ap, CA | 200 ft | Jan 31 | Dec 11 |
| Pismo Beach, CA | 39 ft | Feb 1 | Jan 4 |
Frost dates near Morro Bay
- Morro Bay, CA 93442 · last Jan 19, first Jan 14
- Los Osos, CA 93402 · last Jan 19, first Jan 14
- Cayucos, CA 93430 · last Jan 19, first Jan 14
- Atascadero, CA 93423 · last Mar 15, first Nov 10
- San Luis Obispo, CA 93405 · last Jan 16, first Dec 25
- Harmony, CA 93435 · last Jan 19, first Jan 14
- Avila Beach, CA 93424 · last Feb 1, first Jan 4
- Templeton, CA 93465 · last Mar 15, first Nov 10
Frequently asked questions
- When is the last frost in Morro Bay, CA?
- Frost occurs in about 15% of years at the nearest NOAA station (Morro Bay Fire Dept, CA), so there is no reliable average last frost date.
- When is the first frost in Morro Bay, CA?
- Frost occurs in about 15% 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.