Frost dates for 95485Upper Lake, CA
The average last spring frost in Upper Lake is April 8 and the average first fall frost is November 6, giving a typical growing season of about 211 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 8
- Average first fall frost
- Nov 6
- Growing season
- 211 days
Safer after Apr 29 (1-in-10 risk)
Possible by Oct 20 (1-in-10 risk)
First frost typically in 7 days
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) | Apr 15 · May 2 · May 25 | Oct 2 · Oct 21 · Nov 6 | 171 days | 100% |
| Frost / freeze (32°F) | Mar 11 · Apr 8 · Apr 29 | Oct 20 · Nov 6 · Nov 24 | 211 days | 100% |
| Hard freeze (28°F) | Jan 25 · Feb 28 · Apr 2 | Nov 3 · Nov 22 · Dec 12 | 268 days | 100% |
Planting calendar for Upper Lake
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 8 – May 14 |
| Tomatoes | Transplant outdoors | Apr 24 – Jul 17 |
| Peppers | Start seeds indoors | Mar 8 – Apr 8 |
| Peppers | Transplant outdoors | May 8 – Jun 8 |
| Eggplant | Start seeds indoors | Mar 25 – Apr 23 |
| Eggplant | Transplant outdoors | May 8 – Jun 8 |
| Cucumbers | Sow outdoors | May 8 – Jul 27 |
| Summer squash | Sow outdoors | Apr 24 – Jun 8 |
| Winter squash & pumpkins | Sow outdoors | May 8 – Jun 8 |
| Snap beans | Sow outdoors | Apr 24 – Aug 19 |
| Sweet corn | Sow outdoors | Apr 24 – Jul 17 |
| Watermelon & cantaloupe | Sow outdoors | May 8 – Jun 8 |
| Okra | Sow outdoors | May 1 – May 24 |
| Peas | Sow outdoors (spring) | Mar 8 – Apr 23 |
| Potatoes | Plant outdoors (spring) | Mar 8 – May 8 |
| Onions | Start seeds indoors (spring) | Jan 25 – Feb 21 |
| Onions | Transplant outdoors (spring) | Mar 25 – Apr 23 |
| Broccoli | Start seeds indoors (spring) | Feb 18 – Mar 24 |
| Broccoli | Transplant outdoors (spring) | Mar 25 – Apr 23 |
| Broccoli | Start seeds indoors (fall) | Jul 7 – Jul 17 |
| Broccoli | Transplant outdoors (fall) | Aug 6 – Aug 17 |
| Cabbage | Start seeds indoors (spring) | Feb 8 – Mar 8 |
| Cabbage | Transplant outdoors (spring) | Mar 8 – Apr 8 |
| Cabbage | Start seeds indoors (fall) | Jun 27 – Jul 27 |
| Cabbage | Transplant outdoors (fall) | Jul 27 – Aug 27 |
| Leaf lettuce | Sow outdoors (spring) | Mar 8 – May 24 |
| Leaf lettuce | Sow outdoors (fall) | Jul 27 – Sep 12 |
| Spinach | Sow outdoors (spring) | Mar 1 – Apr 14 |
| Spinach | Sow outdoors (fall) | Aug 13 – Sep 17 |
| Radishes | Sow outdoors (spring) | Mar 8 – Apr 28 |
| Radishes | Sow outdoors (fall) | Jul 27 – Sep 27 |
| Kale | Sow outdoors (spring) | Mar 25 – Apr 14 |
| Kale | Sow outdoors (fall) | Jul 20 – Aug 27 |
| Carrots | Sow outdoors (spring) | Apr 8 – May 24 |
| Carrots | Sow outdoors (fall) | Jun 27 – Aug 12 |
| Garlic | Plant outdoors (fall) | Oct 27 – Nov 27 |
Where these dates come from
ZIP code 95485 is matched to the NOAA station Potter Valley Powerhouse, CA, 27.3 km away, at 1,018 ft elevation (491 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Potter Valley Powerhouse, CA (used) | 1,018 ft | Apr 8 | Nov 6 |
| Ukiah Muni Ap, CA | 601 ft | Mar 5 | Nov 21 |
| Ukiah, CA | 636 ft | Mar 19 | Nov 20 |
| East Park Rsvr, CA | 1,205 ft | Apr 6 | Nov 10 |
Frost dates near Upper Lake
- Witter Springs, CA 95493 · last Apr 8, first Nov 6
- Nice, CA 95464 · last Apr 10, first Nov 6
- Lakeport, CA 95453 · last Apr 10, first Nov 6
- Lucerne, CA 95458 · last Apr 10, first Nov 6
- Finley, CA 95435 · last Apr 10, first Nov 6
- Talmage, CA 95481 · last Mar 5, first Nov 21
- Glenhaven, CA 95443 · last Apr 10, first Nov 6
- Ukiah, CA 95482 · last Mar 19, first Nov 20
Frequently asked questions
- When is the last frost in Upper Lake, CA?
- For ZIP code 95485, the average last spring frost (32°F) is April 8, based on NOAA 1991-2020 climate normals for the Potter Valley Powerhouse, CA weather station. There is a 1-in-10 chance of a frost after April 29.
- When is the first frost in Upper Lake, CA?
- The average first fall frost (32°F) is November 6. There is a 1-in-10 chance of frost by October 20, so tender plants are at risk from that point on.
- How long is the growing season in 95485?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 211 days long.
- 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.