Frost dates for Johnson Valley, CA
At Johnson Valley, the median last spring frost (32°F) is Mar 1 and the median first fall frost is Nov 29, for a typical growing season of 271 days. For a 90% chance that the last frost has passed, wait until Mar 29. Nearby ZIP codes are in USDA hardiness zone 9a.
- Mar 1Last spring frost (median)50% chance of 32°F after this date
- Mar 29Safer planting date10% chance of 32°F after this date
- Nov 29First fall frost (median)50% chance of 32°F by this date
- 271 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 | Mar 28 | Apr 19 |
| 32°F | Jan 24 | Mar 1 | Mar 29 |
| 28°F | Dec 22 | Jan 30 | Feb 28 |
| 24°F | Dec 12 | Jan 1 | 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 28 | Nov 16 | Dec 1 |
| 32°F | Nov 11 | Nov 29 | Dec 14 |
| 28°F | Nov 24 | Dec 10 | Dec 29 |
| 24°F | Dec 6 | Dec 22 | 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 | 202 days | 231 days | 258 days |
| 32°F | 236 days | 271 days | 308 days |
| 28°F | 278 days | 318 days | 352 days |
| 24°F | 324 days | 357 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 97% |
| 24°F | 64% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 92285 | 9a | 20 to 25°F | 3 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 USC00044394, at 34.3592, -116.5378, elevation 965 m (3,167 ft).
- Data quality: Representative (10+ years), 12 years of freeze data.
- Average days per year at or below 32°F: 28.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Yucca Mesa (20 km)
- Yucca Valley (29 km)
- Morongo Valley N (30 km)
- Joshua Tree (34 km)
- Big Bear Lake (37 km)
- Twentynine Palms (53 km)
- Palm Springs Regional Airport (59 km)
- Palm Springs (59 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.