Sylvania, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.7 °C (low) to 15.2 °C (high). Annual precipitation averages 904 Millimeters. Sylvania 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.8 °C | 0.3 °C | 60.96 mm |
| February | -7.1 °C | 1.9 °C | 54.36 mm |
| March | -2.7 °C | 7.3 °C | 63.75 mm |
| April | 3.4 °C | 14.7 °C | 88.14 mm |
| May | 9.8 °C | 21.1 °C | 96.52 mm |
| June | 15.2 °C | 26.6 °C | 90.17 mm |
| July | 17 °C | 28.8 °C | 85.09 mm |
| August | 15.9 °C | 27.6 °C | 86.11 mm |
| September | 11.8 °C | 24.3 °C | 74.93 mm |
| October | 5.6 °C | 17.3 °C | 72.64 mm |
| November | 0.2 °C | 9.5 °C | 71.63 mm |
| December | -4.4 °C | 3.1 °C | 59.69 mm |
| Annual | 4.7 °C | 15.2 °C | 903.99 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |