Hawthorn, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 38.6 °F (low) to 60.5 °F (high). Annual precipitation averages 45.8 Inches. Hawthorn 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 | 18.3 °F | 35.2 °F | 3.59 in. |
| February | 18.8 °F | 38.2 °F | 2.63 in. |
| March | 25.7 °F | 47.4 °F | 3.6 in. |
| April | 35.5 °F | 61.4 °F | 3.96 in. |
| May | 46.1 °F | 71.9 °F | 3.98 in. |
| June | 55.4 °F | 79.0 °F | 4.72 in. |
| July | 59.3 °F | 82.7 °F | 4.65 in. |
| August | 58.1 °F | 82.0 °F | 4.12 in. |
| September | 51.0 °F | 75.1 °F | 4.08 in. |
| October | 39.9 °F | 62.9 °F | 3.31 in. |
| November | 30.9 °F | 50.4 °F | 3.59 in. |
| December | 24.0 °F | 39.5 °F | 3.57 in. |
| Annual | 38.6 °F | 60.5 °F | 45.8 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 |