| 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 Zone 5b: -15°F to -10°F | |
| 1990 Hardiness Zone: | Zone 6b: -5F to 0F | |
| Average First Frost Date: | Oct. 1 - Oct. 10 | |
| Average Last Frost Date: | May 11 - May 20 | |
| Koppen-Geiger Climate Zone: | BSk - Cold Semi-Arid Climate | |
| Ecoregion: | 10c - Umatilla Plateau | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 97836 - Heppner, OR | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 24 | 28 | 32 | 36 | 42 | 47 | 52 | 52 | 45 | 38 | 31 | 26 | 38 |
| Avg Max Temp (°F) | 41 | 46 | 53 | 60 | 68 | 76 | 85 | 85 | 75 | 64 | 49 | 41 | 62 |
| Avg Precip (In.) | 1.46 | 1.24 | 1.58 | 1.38 | 1.7 | 1.03 | .35 | .55 | .67 | 1.12 | 1.79 | 1.33 | 14.2 |