| 2023 Hardiness Zone: | 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 1b: -15F to -10F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | Apr. 21 - Apr. 30 |
| Koppen-Geiger Climate Zone: | Dsb - Humid Continental Climate - Dry Cool Summer |
| Ecoregion: | 15s - Spokane Valley Outwash Plains |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 99217 - Spokane, WA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 23 | 27 | 31 | 36 | 43 | 49 | 54 | 54 | 45 | 36 | 30 | 25 | 38 |
| Avg Max Temp (°F) | 34 | 42 | 50 | 59 | 68 | 75 | 84 | 84 | 74 | 60 | 43 | 36 | 59 |
| Avg Precip (In.) | 1.86 | 1.76 | 1.97 | 1.38 | 1.91 | 1.57 | 1.07 | .73 | .93 | 1.32 | 2.67 | 2.36 | 19.54 |