Last spring frost
Mar 19
Frost Dates for Comptche, CA
First fall frost
Nov 20
Growing season
245 days
Hardiness zone
9b
In an average year around Comptche, CA, the last spring frost (32°F) is about Mar 19 and the first fall frost is about Nov 20, giving roughly a 245-day growing season. To be safe most years, wait until Feb 13 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 9 | Apr 17 | Mar 31 |
| Freeze (32°F) | Apr 15 | Mar 19 | Feb 13 |
| Hard (28°F) | Mar 13 | Feb 6 | Dec 25 |
| Severe (24°F) | Feb 24 | Jan 7 | Dec 11 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 9 | Apr 30 | Apr 24 | Apr 21 | Apr 17 | Apr 13 | Apr 9 | Apr 5 | Mar 31 |
| 32°F | Apr 15 | Apr 7 | Apr 2 | Mar 27 | Mar 19 | Mar 12 | Mar 4 | Feb 26 | Feb 13 |
| 28°F | Mar 13 | Mar 2 | Feb 23 | Feb 16 | Feb 6 | Jan 30 | Jan 19 | Jan 5 | Dec 25 |
| 24°F | Feb 24 | Jan 31 | Jan 24 | Jan 15 | Jan 7 | Jan 2 | Dec 28 | Dec 20 | Dec 11 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Oct 18 | Nov 2 | Nov 19 |
| Freeze (32°F) | Nov 2 | Nov 20 | Dec 9 |
| Hard (28°F) | Nov 17 | Dec 5 | Jan 6 |
| Severe (24°F) | Nov 30 | Dec 18 | Jan 26 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 18 | Oct 24 | Oct 29 | Nov 1 | Nov 2 | Nov 5 | Nov 9 | Nov 13 | Nov 19 |
| 32°F | Nov 2 | Nov 7 | Nov 12 | Nov 15 | Nov 20 | Nov 24 | Nov 28 | Dec 3 | Dec 9 |
| 28°F | Nov 17 | Nov 23 | Nov 28 | Dec 1 | Dec 5 | Dec 9 | Dec 14 | Dec 24 | Jan 6 |
| 24°F | Nov 30 | Dec 4 | Dec 9 | Dec 13 | Dec 18 | Dec 26 | Jan 1 | Jan 8 | Jan 26 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Ukiah, Ca, about 20.1 miles away@if(!empty($station['elevation_ft'])), at 636 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in Comptche, CA?
On average, the last spring frost (32°F) around Comptche, CA is about Mar 19. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 13.
When is the first frost in the fall?
The first fall frost around Comptche, CA typically arrives about Nov 20. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Mar 19 on average, or Feb 13 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 245 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 95463 Planting calendar → California frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026