Last spring frost
May 3
Frost Dates for San Jose, CA
First fall frost
Nov 18
Growing season
197 days
Hardiness zone
9b
In an average year around San Jose, CA, the last spring frost (32°F) is about May 3 and the first fall frost is about Nov 18, giving roughly a 197-day growing season. To be safe most years, wait until Apr 7 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) | Jun 18 | May 27 | Apr 28 |
| Freeze (32°F) | Jun 5 | May 3 | Apr 7 |
| Hard (28°F) | May 6 | Apr 10 | Feb 23 |
| Severe (24°F) | Apr 11 | Mar 1 | Dec 31 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Jun 18 | Jun 9 | Jun 4 | May 31 | May 27 | May 21 | May 14 | May 7 | Apr 28 |
| 32°F | Jun 5 | May 26 | May 16 | May 9 | May 3 | Apr 29 | Apr 24 | Apr 17 | Apr 7 |
| 28°F | May 6 | Apr 29 | Apr 22 | Apr 15 | Apr 10 | Apr 3 | Mar 27 | Mar 14 | Feb 23 |
| 24°F | Apr 11 | Apr 1 | Mar 25 | Mar 13 | Mar 1 | Feb 21 | Feb 6 | Jan 18 | Dec 31 |
| 20°F | Mar 12 | Feb 27 | Feb 16 | Feb 4 | Jan 27 | Jan 14 | Jan 5 | Dec 31 | Dec 16 |
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 1 | Oct 29 | Nov 23 |
| Freeze (32°F) | Oct 22 | Nov 18 | Dec 12 |
| Hard (28°F) | Nov 10 | Dec 7 | Jan 18 |
| Severe (24°F) | Nov 28 | Jan 1 | Mar 2 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 1 | Oct 10 | Oct 17 | Oct 22 | Oct 29 | Nov 3 | Nov 8 | Nov 15 | Nov 23 |
| 32°F | Oct 22 | Nov 1 | Nov 7 | Nov 13 | Nov 18 | Nov 25 | Dec 1 | Dec 4 | Dec 12 |
| 28°F | Nov 10 | Nov 20 | Nov 29 | Dec 3 | Dec 7 | Dec 12 | Dec 20 | Jan 1 | Jan 18 |
| 24°F | Nov 28 | Dec 7 | Dec 15 | Dec 26 | Jan 1 | Jan 10 | Jan 23 | Feb 8 | Mar 2 |
| 20°F | Dec 9 | Dec 20 | Jan 1 | Jan 4 | Jan 13 | Jan 22 | Jan 31 | Feb 14 | Feb 27 |
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: Mt Hamilton, Ca, about 10.3 miles away@if(!empty($station['elevation_ft'])), at 4,206 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 San Jose, CA?
On average, the last spring frost (32°F) around San Jose, CA is about May 3. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 7.
When is the first frost in the fall?
The first fall frost around San Jose, CA typically arrives about Nov 18. 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 May 3 on average, or Apr 7 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 197 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 95013 Planting calendar → California frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026