Frost dates for Gilroy, CA
At Gilroy, the median last spring frost (32°F) is Feb 24 and the median first fall frost is Nov 27, for a typical growing season of 277 days. For a 90% chance that the last frost has passed, wait until Apr 4. Nearby ZIP codes are in USDA hardiness zone 9b.
- Feb 24Last spring frost (median)50% chance of 32°F after this date
- Apr 4Safer planting date10% chance of 32°F after this date
- Nov 27First fall frost (median)50% chance of 32°F by this date
- 277 daysGrowing season (median)between 32°F freezes
Last spring frost dates
The chance that the temperature drops to the threshold after each date.
| Temperature | 90% chance later | 50% chance later | 10% chance later |
|---|---|---|---|
| 36°F | Mar 4 | Apr 4 | May 1 |
| 32°F | Jan 23 | Feb 24 | Apr 4 |
| 28°F | Dec 22 | Jan 16 | Feb 19 |
| 24°F | Dec 13 | Jan 4 | Jan 24 |
First fall frost dates
The chance that the temperature has dropped to the threshold by each date.
| Temperature | 10% chance by | 50% chance by | 90% chance by |
|---|---|---|---|
| 36°F | Oct 20 | Nov 10 | Nov 29 |
| 32°F | Nov 10 | Nov 27 | Dec 18 |
| 28°F | Nov 24 | Dec 12 | Jan 14 |
| 24°F | Dec 8 | Dec 27 | Jan 19 |
Growing season length
Days between the last spring and first fall freeze, as the length reached in 9, 5 and 1 out of 10 years.
| Temperature | 9 in 10 years at least | 5 in 10 years at least | 1 in 10 years at least |
|---|---|---|---|
| 36°F | 174 days | 218 days | 255 days |
| 32°F | 228 days | 277 days | 317 days |
| 28°F | 295 days | 333 days | 365 days |
| 24°F | 338 days | 365 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 91% |
| 24°F | 49% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 95020 | 9b | 25 to 30°F | 1 km |
| 95046 | 9b | 25 to 30°F | 11 km |
| 95037 | 9b | 25 to 30°F | 18 km |
Not the official USDA Plant Hardiness Zone Map. Zones shown here are the values published in the USDA-ARS / Oregon State University PRISM Group 2023 ZIP code tables, shown unaltered. For the official interactive map, visit planthardiness.ars.usda.gov.
About this station
- NOAA station ID USC00043417, at 37.0031, -121.5608, elevation 59 m (194 ft).
- Data quality: Representative (10+ years), 21 years of freeze data.
- Average days per year at or below 32°F: 16.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Watsonville Wtr Wks (20 km)
- Hollister 2 (21 km)
- Watsonville Muni Airport (22 km)
- Paicines 4 W (37 km)
- Salinas Municipal Airport (38 km)
- Mount Hamilton (39 km)
- Santa Cruz (39 km)
- Salinas #2 (39 km)
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020, annual/seasonal normals by station (version 1.0.1), file dated June 27, 2023; documentation.
- USDA Agricultural Research Service and PRISM Group, Oregon State University, 2023 Plant Hardiness Zone Map ZIP code tables (CONUS, Alaska, Hawaii, Puerto Rico), files dated November 17, 2023. Data © PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed November 1, 2026. Official map: planthardiness.ars.usda.gov.
- U.S. Census Bureau, 2024 Gazetteer ZIP Code Tabulation Areas file, dated August 30, 2024 (ZIP centroids used to find the nearest station).
Freeze dates are 30-year probabilities, not forecasts. Check your local forecast before planting tender plants.