Pen Mar, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42 °F (low) to 61.3 °F (high). Annual precipitation averages 48.1 Inches. Pen Mar is located in USDA Plant Hardiness Zone 7a. 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 | 21.5 °F | 37.1 °F | 3.42 in. |
| February | 22.8 °F | 40.7 °F | 2.67 in. |
| March | 29.4 °F | 48.8 °F | 3.98 in. |
| April | 40.0 °F | 62.2 °F | 4.2 in. |
| May | 49.6 °F | 71.0 °F | 4.9 in. |
| June | 58.6 °F | 79.3 °F | 4.53 in. |
| July | 62.8 °F | 83.2 °F | 4.06 in. |
| August | 61.1 °F | 81.6 °F | 3.86 in. |
| September | 54.3 °F | 75.1 °F | 5.21 in. |
| October | 43.4 °F | 63.8 °F | 4.29 in. |
| November | 33.9 °F | 51.5 °F | 3.39 in. |
| December | 26.3 °F | 41.3 °F | 3.63 in. |
| Annual | 42 °F | 61.3 °F | 48.14 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |