| 2023 Hardiness Zone: | Zone 6b: -5°F to 0°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: | 10a - Channeled Scablands |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 99022 - Medical Lake, WA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 21 | 25 | 30 | 35 | 42 | 48 | 53 | 53 | 45 | 35 | 28 | 22 | 36 |
| Avg Max Temp (°F) | 33 | 40 | 48 | 57 | 66 | 73 | 82 | 82 | 72 | 59 | 41 | 33 | 57 |
| Avg Precip (In.) | 1.66 | 1.58 | 1.66 | 1.25 | 1.63 | 1.28 | .91 | .64 | .82 | 1.14 | 2.38 | 2.1 | 17.02 |