| 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 Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Sep.11 - Sep. 20 |
| Average Last Frost Date: | Jun. 1 - Jun. 10 |
| Koppen-Geiger Climate Zone: | Dsb - Humid Continental Climate - Dry Cool Summer |
| Ecoregion: | 15r - Okanogan-Colville Xeric Valleys and Foothills |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 99181 - Valley, WA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 19 | 23 | 28 | 33 | 40 | 46 | 50 | 49 | 41 | 32 | 28 | 21 | 34 |
| Avg Max Temp (°F) | 33 | 40 | 50 | 60 | 69 | 76 | 84 | 85 | 75 | 60 | 41 | 33 | 59 |
| Avg Precip (In.) | 2.33 | 2.19 | 2.21 | 1.63 | 2.16 | 1.8 | 1.2 | .97 | 1.03 | 1.27 | 2.95 | 2.97 | 22.69 |