The last 36°F Spring frost date is 30% likely to be on Feb 1. (See detailed probabilities below.)
The last 32°F light freeze date is 30% likely to be on Jan 21. (See detailed probabilities below.)
(See also 🍂 First Fall Frost Dates.)
Last frost date probabilities for San Bruno, CA are based on historical climate data.
Always check your local forecast for the most up-to-date frost warnings.
Book Recommendations (ads!)
📚 Growing Under Cover: Techniques for a More Productive, Weather-Resistant, Pest-Free Vegetable Garden
The last spring frost signals when your area is safe from freezing temperatures. Tender plants can now grow outdoors without cold damage! This marks the beginning of the growing season. Last spring frost serves as your essential starting point for planting warm-season crops. It's also time to remove winter protection from your perennials. Enjoy the longer days and warmer weather!
Start seeds indoors several weeks before your last frost date. This gives plants time to reach transplanting size when weather permits. Plan your outdoor planting schedule around your area's average last frost date. Plant some crops before and some after this date to protect against weather changes. Look for spots in your yard where frost stays longer or disappears earlier. Create your own frost map to use all available growing space and extend your season. Keep watching your local weather forecast to catch any surprise late frosts.
| Probability of frost (36°F) on or after… | |
|---|---|
| 10% chance | Feb 23 |
| 20% chance | Feb 9 |
| 30% chance | Feb 1 |
| 40% chance | Jan 27 |
| 50% chance | Jan 20 |
| 60% chance | Jan 10 |
| 70% chance | Jan 5 |
| 80% chance | Dec 31 |
| 90% chance | Dec 21 |
| Probability of light freeze (32°F) on or after… | |
|---|---|
| 10% chance | Jan 31 |
| 20% chance | Jan 27 |
| 30% chance | Jan 21 |
| 40% chance | Jan 12 |
| 50% chance | Jan 6 |
| 60% chance | Jan 3 |
| 70% chance | Dec 31 |
| 80% chance | Dec 25 |
| 90% chance | Dec 17 |
| Probability of moderate freeze (28°F) on or after… | |
|---|---|
| 10% chance | rarely |
| 20% chance | rarely |
| 30% chance | rarely |
| 40% chance | rarely |
| 50% chance | rarely |
| 60% chance | rarely |
| 70% chance | rarely |
| 80% chance | rarely |
| 90% chance | rarely |
| Probability of moderate hard freeze (24°F) on or after… | |
|---|---|
| 10% chance | rarely |
| 20% chance | rarely |
| 30% chance | rarely |
| 40% chance | rarely |
| 50% chance | rarely |
| 60% chance | rarely |
| 70% chance | rarely |
| 80% chance | rarely |
| 90% chance | rarely |
| Probability of hard freeze (20°F) on or after… | |
|---|---|
| 10% chance | rarely |
| 20% chance | rarely |
| 30% chance | rarely |
| 40% chance | rarely |
| 50% chance | rarely |
| 60% chance | rarely |
| 70% chance | rarely |
| 80% chance | rarely |
| 90% chance | rarely |
| Probability of severe hard freeze (16°F) on or after… | |
|---|---|
| 10% chance | rarely |
| 20% chance | rarely |
| 30% chance | rarely |
| 40% chance | rarely |
| 50% chance | rarely |
| 60% chance | rarely |
| 70% chance | rarely |
| 80% chance | rarely |
| 90% chance | rarely |
Agricultural climatic data from weather station: PACIFICA 4 SSE (USC00046599)