Frost dates for Big Bar 4 E, CA
At Big Bar 4 E, the median last spring frost (32°F) is Apr 16 and the median first fall frost is Oct 31, for a typical growing season of 197 days. For a 90% chance that the last frost has passed, wait until May 3. Nearby ZIP codes are in USDA hardiness zones 8b to 9a.
- Apr 16Last spring frost (median)50% chance of 32°F after this date
- May 3Safer planting date10% chance of 32°F after this date
- Oct 31First fall frost (median)50% chance of 32°F by this date
- 197 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 21 | May 6 | May 29 |
| 32°F | Mar 23 | Apr 16 | May 3 |
| 28°F | Feb 2 | Mar 17 | Apr 16 |
| 24°F | Dec 12 | Jan 31 | Mar 8 |
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 | Sep 27 | Oct 14 | Nov 1 |
| 32°F | Oct 13 | Oct 31 | Nov 26 |
| 28°F | Oct 24 | Nov 19 | Dec 20 |
| 24°F | Nov 7 | Dec 9 | Jan 28 |
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 | 129 days | 157 days | 182 days |
| 32°F | 170 days | 197 days | 231 days |
| 28°F | 205 days | 245 days | 296 days |
| 24°F | 257 days | 313 days | 364 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 100% |
| 28°F | 100% |
| 24°F | 88% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 96046 | 8b | 15 to 20°F | 24 km |
| 96041 | 8b | 15 to 20°F | 25 km |
| 95527 | 8b | 15 to 20°F | 29 km |
| 95563 | 9a | 20 to 25°F | 35 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 USC00040738, at 40.7406, -123.2078, elevation 382 m (1,253 ft).
- Data quality: Representative (10+ years), 22 years of freeze data.
- Average days per year at or below 32°F: 59.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Weaverville (23 km)
- Trinity River Hatchery (35 km)
- Cecilville (45 km)
- Redding 12 WNW (52 km)
- Whiskeytown Rsvr (59 km)
- Grizzly Creek State Park (66 km)
- Shasta Dam (67 km)
- Orleans (69 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.