Northfield, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.9 °F (low) to 59.1 °F (high). Annual precipitation averages 42.5 Inches. Northfield 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 | 18.9 °F | 33.7 °F | 3.02 in. |
| February | 19.6 °F | 36.0 °F | 2.34 in. |
| March | 26.9 °F | 44.9 °F | 3.31 in. |
| April | 38.6 °F | 58.2 °F | 3.89 in. |
| May | 49.3 °F | 70.3 °F | 4.15 in. |
| June | 58.4 °F | 78.4 °F | 4.17 in. |
| July | 62.4 °F | 82.7 °F | 4.13 in. |
| August | 60.5 °F | 80.9 °F | 3.78 in. |
| September | 53.6 °F | 74.3 °F | 3.9 in. |
| October | 43.3 °F | 61.8 °F | 3.54 in. |
| November | 34.1 °F | 49.3 °F | 3.15 in. |
| December | 25.4 °F | 38.2 °F | 3.09 in. |
| Annual | 40.9 °F | 59.1 °F | 42.47 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 |