Mainville, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 5 °C (low) to 16.6 °C (high). Annual precipitation averages 1153.4 Millimeters. Mainville is located in USDA Plant Hardiness Zone 6b. 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 | -6.7 °C | 2.4 °C | 82.3 mm |
| February | -5.9 °C | 4 °C | 62.48 mm |
| March | -1.9 °C | 9.2 °C | 86.11 mm |
| April | 3.6 °C | 16.9 °C | 99.82 mm |
| May | 9.2 °C | 22.7 °C | 100.08 mm |
| June | 14.4 °C | 27.1 °C | 115.06 mm |
| July | 16.8 °C | 29.6 °C | 112.01 mm |
| August | 15.8 °C | 28.6 °C | 102.36 mm |
| September | 11.8 °C | 24.8 °C | 120.65 mm |
| October | 5.7 °C | 17.9 °C | 104.14 mm |
| November | 0.6 °C | 11 °C | 82.04 mm |
| December | -3.6 °C | 5.1 °C | 86.36 mm |
| Annual | 5 °C | 16.6 °C | 1153.41 mm |
| 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 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |