Willoughby Hills, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42 °F (low) to 58.2 °F (high). Annual precipitation averages 44.7 Inches. Willoughby Hills is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 20.1 °F | 34.0 °F | 3.37 in. |
| February | 20.6 °F | 36.1 °F | 2.39 in. |
| March | 27.4 °F | 44.4 °F | 3.1 in. |
| April | 38.5 °F | 57.0 °F | 3.65 in. |
| May | 49.5 °F | 67.8 °F | 3.9 in. |
| June | 59.1 °F | 76.7 °F | 3.98 in. |
| July | 63.4 °F | 80.3 °F | 4.45 in. |
| August | 62.2 °F | 79.0 °F | 4.05 in. |
| September | 55.6 °F | 73.1 °F | 4.26 in. |
| October | 45.2 °F | 61.3 °F | 4.28 in. |
| November | 35.2 °F | 49.7 °F | 3.69 in. |
| December | 26.7 °F | 39.1 °F | 3.58 in. |
| Annual | 42 °F | 58.2 °F | 44.7 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |