North Royalton, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.6 °C (low) to 14.8 °C (high). Annual precipitation averages 1148.6 Millimeters. North Royalton is located in USDA Plant Hardiness Zone 6a. 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 | -7.7 °C | 0.4 °C | 80.26 mm |
| February | -7.2 °C | 1.8 °C | 61.47 mm |
| March | -2.9 °C | 7.2 °C | 95 mm |
| April | 3.4 °C | 14.7 °C | 107.44 mm |
| May | 9.2 °C | 21.1 °C | 113.03 mm |
| June | 14.4 °C | 25.7 °C | 109.22 mm |
| July | 16.5 °C | 28.1 °C | 102.62 mm |
| August | 15.4 °C | 27.2 °C | 106.43 mm |
| September | 11.6 °C | 23.4 °C | 107.7 mm |
| October | 5.8 °C | 16.2 °C | 98.04 mm |
| November | 0.6 °C | 9.3 °C | 85.09 mm |
| December | -4.3 °C | 3 °C | 82.3 mm |
| Annual | 4.6 °C | 14.8 °C | 1148.6 mm |
| 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 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |