| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F Zone 7a: 0°F to 5°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F |
| 1990 Hardiness Zone: | Zone 6a: -10F to -5F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate |
| Ecoregion: | 80f - Owyhee Uplands and Canyons |
| Heat Zone Days: | 46 - 60 days Over 86°F |
Annual Climate Data for ZIP Code 97920 - Westfall, OR | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 19 | 24 | 29 | 34 | 42 | 48 | 55 | 54 | 45 | 35 | 26 | 19 | 36 |
| Avg Max Temp (°F) | 37 | 44 | 54 | 62 | 70 | 79 | 89 | 88 | 78 | 65 | 46 | 37 | 62 |
| Avg Precip (In.) | 1.25 | .97 | .94 | .83 | 1.18 | .95 | .46 | .48 | .43 | .55 | 1.13 | 1.34 | 10.51 |