Hermitage, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 39.6 °F (low) to 60.6 °F (high). Annual precipitation averages 41.8 Inches. Hermitage is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.5 °F | 34.8 °F | 2.9 in. |
| February | 19.1 °F | 37.7 °F | 2.3 in. |
| March | 26.8 °F | 47.0 °F | 2.92 in. |
| April | 37.1 °F | 61.0 °F | 3.79 in. |
| May | 47.4 °F | 71.6 °F | 3.86 in. |
| June | 56.4 °F | 79.8 °F | 4.51 in. |
| July | 60.4 °F | 83.6 °F | 4.49 in. |
| August | 58.7 °F | 82.2 °F | 3.64 in. |
| September | 52.1 °F | 75.8 °F | 4.03 in. |
| October | 41.3 °F | 63.5 °F | 3.2 in. |
| November | 32.5 °F | 50.3 °F | 3.0 in. |
| December | 24.7 °F | 39.6 °F | 3.17 in. |
| Annual | 39.6 °F | 60.6 °F | 41.81 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |