| 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 7a: 0°F to 5°F |
| 1990 Hardiness Zone: | Zone 6a: -10F to -5F |
| Average First Frost Date: | July 21 - July 31 |
| Average Last Frost Date: | Jun. 21 - Jun. 30 |
| Koppen-Geiger Climate Zone: | Dsb - Humid Continental Climate - Dry Cool Summer |
| Ecoregion: | 9d - Ponderosa Pine/Bitterbrush Woodland |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 97759 - Sisters, OR | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 20 | 23 | 26 | 29 | 34 | 39 | 42 | 42 | 35 | 29 | 26 | 21 | 30 |
| Avg Max Temp (°F) | 39 | 44 | 50 | 57 | 65 | 74 | 84 | 84 | 75 | 63 | 46 | 39 | 60 |
| Avg Precip (In.) | 2.19 | 1.63 | 1.14 | .88 | .8 | .61 | .45 | .5 | .47 | .94 | 2.02 | 2 | 13.63 |