Frost dates for Ben Lomond #4, CA
At Ben Lomond #4, the median last spring frost (32°F) is Mar 25 and the median first fall frost is Nov 11, for a typical growing season of 231 days. For a 90% chance that the last frost has passed, wait until Apr 21. Nearby ZIP codes are in USDA hardiness zones 9a to 9b.
- Mar 25Last spring frost (median)50% chance of 32°F after this date
- Apr 21Safer planting date10% chance of 32°F after this date
- Nov 11First fall frost (median)50% chance of 32°F by this date
- 231 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 | Apr 6 | Apr 28 | May 19 |
| 32°F | Feb 17 | Mar 25 | Apr 21 |
| 28°F | Dec 26 | Feb 6 | Mar 9 |
| 24°F | Dec 13 | Jan 4 | Feb 13 |
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 1 | Oct 21 | Nov 11 |
| 32°F | Oct 18 | Nov 11 | Dec 4 |
| 28°F | Nov 11 | Dec 4 | Jan 7 |
| 24°F | Dec 1 | Dec 20 | Jan 23 |
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 | 144 days | 179 days | 207 days |
| 32°F | 197 days | 231 days | 272 days |
| 28°F | 262 days | 302 days | 344 days |
| 24°F | 317 days | 355 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 96% |
| 24°F | 57% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 95005 | 9a | 20 to 25°F | 2 km |
| 95018 | 9b | 25 to 30°F | 2 km |
| 95007 | 9b | 25 to 30°F | 4 km |
| 95041 | 9a | 20 to 25°F | 4 km |
| 95066 | 9b | 25 to 30°F | 6 km |
| 95006 | 9b | 25 to 30°F | 11 km |
| 95017 | 9b | 25 to 30°F | 14 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 USC00040673, at 37.0856, -122.0797, elevation 128 m (420 ft).
- Data quality: Representative (10+ years), 17 years of freeze data.
- Average days per year at or below 32°F: 37.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Santa Cruz (13 km)
- Los Gatos (19 km)
- Skyline Ridge Preserve (27 km)
- Watsonville Muni Airport (31 km)
- Watsonville Wtr Wks (33 km)
- San Jose (33 km)
- San Jose (33 km)
- San Gregorio 2 SE (35 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.