John Day, Oregon has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 34.1 °F (low) to 63 °F (high). Annual precipitation averages 12.6 Inches. John Day is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 23.1 °F | 42.2 °F | 1.01 in. |
| February | 24.4 °F | 46.5 °F | 0.68 in. |
| March | 28.2 °F | 53.2 °F | 1.25 in. |
| April | 32.1 °F | 59.3 °F | 1.49 in. |
| May | 38.5 °F | 68.3 °F | 1.92 in. |
| June | 44.1 °F | 76.5 °F | 1.34 in. |
| July | 49.0 °F | 88.7 °F | 0.48 in. |
| August | 47.4 °F | 88.2 °F | 0.48 in. |
| September | 40.5 °F | 79.2 °F | 0.47 in. |
| October | 32.8 °F | 64.5 °F | 1.11 in. |
| November | 27.2 °F | 49.4 °F | 1.21 in. |
| December | 22.2 °F | 40.5 °F | 1.14 in. |
| Annual | 34.1 °F | 63 °F | 12.58 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |