Frost dates for 93442 — Morro Bay, CA
Frost is light and occasional here — typically a few cold nights around midwinter (about 3 a year). Cover tender plants when frost is forecast.
How Morro Bay compares
- In a typical year, frost nights in Morro Bay fall between January 14 and January 19. In 1 year in 10 the first frost comes as early as December 25, or the last frost as late as February 9.
- Compared with Santa Maria, CA, 62 km away, the last frost here is 16 days earlier than there.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | December 30 |
| 50% (median) | January 19 |
| 10% (safe for tender plants) | February 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | December 25 |
| 50% (median) | January 14 |
| 90% (late) | February 8 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Gardening where frost is rare
Morro Bay, CA only freezes on a few winter nights, so the usual "plant after the last frost" rule doesn't apply. Heat and rainfall decide the seasons instead:
- Cool-season crops (lettuce, broccoli, peas, carrots) grow best from fall through late winter.
- Warm-season crops (tomatoes, peppers, beans, squash) do best planted in late winter to spring, and again in late summer for a fall crop — midsummer heat can stop tomatoes setting fruit.
- Heat lovers (okra, sweet potatoes, melons) can be planted through spring and early summer.
About these dates
Based on 1991–2020 NOAA climate normals for the Morro Bay Fire Dept, CA weather station, about 1 km away (elevation 118 ft (36 m)).
ZIP codes in Morro Bay: 93442 93443
Frost dates near Morro Bay
- Los Osos Jan 19 · Jan 14
- Cayucos Jan 19 · Jan 14
- Atascadero Jan 19 · Jan 14
- Harmony Jan 19 · Jan 14
- San Luis Obispo Jan 16 · Dec 25
- Templeton Mar 15 · Nov 10
- Avila Beach Feb 1 · Jan 4
- Cambria Feb 13 · Feb 1
Frequently asked questions
When is the last frost in Morro Bay, CA?
The median last spring frost in Morro Bay, CA is January 19. There is still about a 10% chance of frost after February 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Morro Bay, CA?
The median first fall frost is January 14, with about a 10% chance of frost before December 25.
How long is the growing season in Morro Bay, CA?
About 360 days between the median last spring frost and first fall frost.
What planting zone is Morro Bay, CA?
Morro Bay, CA is in USDA hardiness zone 9b.