Sylvania, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.8 °F (low) to 57.3 °F (high). Annual precipitation averages 38.5 Inches. Sylvania is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 14.2 °F | 32.0 °F | 2.61 in. |
| February | 14.9 °F | 34.7 °F | 1.96 in. |
| March | 22.0 °F | 43.0 °F | 2.97 in. |
| April | 32.5 °F | 56.5 °F | 3.35 in. |
| May | 43.6 °F | 68.4 °F | 3.47 in. |
| June | 52.6 °F | 76.3 °F | 3.91 in. |
| July | 56.9 °F | 80.6 °F | 3.51 in. |
| August | 55.6 °F | 79.2 °F | 3.5 in. |
| September | 48.5 °F | 72.4 °F | 4.13 in. |
| October | 38.0 °F | 59.9 °F | 3.56 in. |
| November | 29.0 °F | 47.2 °F | 2.79 in. |
| December | 21.2 °F | 36.8 °F | 2.71 in. |
| Annual | 35.8 °F | 57.3 °F | 38.47 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |