| 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 Zone 7a: 0°F to 5°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: | Dsb - Humid Continental Climate - Dry Cool Summer |
| Ecoregion: | 10m - Okanogan Valley |
| Heat Zone Days: | 31 - 45 days Over 86°F |
Annual Climate Data for ZIP Code 98812 - Brewster, WA | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 18 | 23 | 30 | 36 | 44 | 51 | 56 | 55 | 47 | 36 | 28 | 19 | 37 |
| Avg Max Temp (°F) | 32 | 39 | 52 | 63 | 71 | 79 | 86 | 87 | 78 | 62 | 44 | 33 | 60 |
| Avg Precip (In.) | 1.2 | 1.14 | .91 | .67 | .87 | .91 | .43 | .44 | .47 | .61 | 1.41 | 1.57 | 10.62 |