| 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. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dsb - Humid Continental Climate - Dry Cool Summer |
| Ecoregion: | 15s - Spokane Valley Outwash Plains |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 99223 - 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 | 55 | 54 | 46 | 37 | 30 | 25 | 38 |
| Avg Max Temp (°F) | 35 | 42 | 50 | 59 | 67 | 74 | 83 | 84 | 74 | 60 | 43 | 36 | 59 |
| Avg Precip (In.) | 1.77 | 1.65 | 1.83 | 1.38 | 1.94 | 1.3 | 1.03 | .74 | .91 | 1.18 | 2.5 | 2.44 | 18.66 |