Mount Union, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.9 °F (low) to 62.5 °F (high). Annual precipitation averages 40.6 Inches. Mount Union is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 20.5 °F | 37.4 °F | 2.78 in. |
| February | 21.6 °F | 40.8 °F | 2.32 in. |
| March | 28.3 °F | 49.5 °F | 3.39 in. |
| April | 38.2 °F | 62.7 °F | 3.6 in. |
| May | 48.5 °F | 73.0 °F | 3.92 in. |
| June | 57.7 °F | 80.9 °F | 3.98 in. |
| July | 61.9 °F | 85.4 °F | 3.35 in. |
| August | 60.5 °F | 83.8 °F | 3.54 in. |
| September | 53.3 °F | 76.9 °F | 4.02 in. |
| October | 41.8 °F | 64.8 °F | 3.57 in. |
| November | 32.6 °F | 52.9 °F | 2.91 in. |
| December | 25.6 °F | 41.5 °F | 3.17 in. |
| Annual | 40.9 °F | 62.5 °F | 40.55 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |