Holley, Oregon has a Warm-Summer Mediterranean Climate climate (Köppen classification: Csb). Average annual temperatures range from 42.1 °F (low) to 63 °F (high). Annual precipitation averages 50.6 Inches. Holley is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 34.4 °F | 46.9 °F | 6.99 in. |
| February | 34.7 °F | 50.8 °F | 5.45 in. |
| March | 36.7 °F | 55.2 °F | 5.93 in. |
| April | 39.6 °F | 60.4 °F | 4.66 in. |
| May | 44.5 °F | 67.1 °F | 3.17 in. |
| June | 48.5 °F | 72.6 °F | 2.04 in. |
| July | 52.0 °F | 81.6 °F | 0.43 in. |
| August | 51.6 °F | 82.6 °F | 0.54 in. |
| September | 47.9 °F | 76.4 °F | 1.66 in. |
| October | 42.6 °F | 64.4 °F | 4.21 in. |
| November | 37.9 °F | 52.2 °F | 7.17 in. |
| December | 34.2 °F | 45.9 °F | 8.35 in. |
| Annual | 42.1 °F | 63 °F | 50.6 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Csb - Warm-Summer Mediterranean Climate |