Frost dates for Willows 6 W, CA
At Willows 6 W, the median last spring frost (32°F) is Feb 21 and the median first fall frost is Dec 6, for a typical growing season of 289 days. For a 90% chance that the last frost has passed, wait until Apr 9. Nearby ZIP codes are in USDA hardiness zone 9b.
- Feb 21Last spring frost (median)50% chance of 32°F after this date
- Apr 9Safer planting date10% chance of 32°F after this date
- Dec 6First fall frost (median)50% chance of 32°F by this date
- 289 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 | Feb 25 | Apr 2 | Apr 25 |
| 32°F | Jan 4 | Feb 21 | Apr 9 |
| 28°F | Dec 14 | Jan 5 | Feb 24 |
| 24°F | Dec 9 | Dec 29 | Jan 20 |
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 | Nov 7 | Nov 23 | Dec 7 |
| 32°F | Nov 16 | Dec 6 | Dec 29 |
| 28°F | Nov 30 | Dec 18 | Jan 27 |
| 24°F | Dec 8 | Dec 25 | Jan 18 |
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 | 205 days | 233 days | 275 days |
| 32°F | 235 days | 289 days | 334 days |
| 28°F | 303 days | 348 days | 365 days |
| 24°F | 355 days | 365 days | 365 days |
Chance of a freeze in any year
| Temperature | Chance per year |
|---|---|
| 36°F | 100% |
| 32°F | 99% |
| 28°F | 70% |
| 24°F | 18% |
ZIP codes whose closest station is this one
| ZIP | Hardiness zone | Avg. extreme low | Distance |
|---|---|---|---|
| 95988 | 9b | 25 to 30°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 USC00049699, at 39.5231, -122.3047, elevation 71 m (234 ft).
- Data quality: Representative (10+ years), 27 years of freeze data.
- Average days per year at or below 32°F: 23.
- Frost risk changes over short distances. Valleys and low spots freeze earlier than hillsides and city centers.
Nearby weather stations
- Stony Gorge Rsvr (21 km)
- East Park Rsvr (26 km)
- Orland (26 km)
- Colusa 2 SSW (44 km)
- Chico Univ Farm (45 km)
- Oroville Muni Airport (59 km)
- Paradise (64 km)
- Oroville (64 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.