Zion, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.9 °C (low) to 15.4 °C (high). Annual precipitation averages 1105.7 Millimeters. Zion 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.7 °C | 1.4 °C | 74.42 mm |
| February | -7.1 °C | 3.2 °C | 61.21 mm |
| March | -3.2 °C | 8.1 °C | 88.9 mm |
| April | 2.7 °C | 15.7 °C | 87.38 mm |
| May | 8.4 °C | 21.7 °C | 116.33 mm |
| June | 13.5 °C | 25.8 °C | 98.04 mm |
| July | 15.8 °C | 28.3 °C | 105.16 mm |
| August | 14.8 °C | 27.3 °C | 109.22 mm |
| September | 10.7 °C | 23.3 °C | 102.87 mm |
| October | 4.6 °C | 16.7 °C | 100.58 mm |
| November | -0.6 °C | 10 °C | 78.74 mm |
| December | -4.6 °C | 3.8 °C | 82.8 mm |
| Annual | 3.9 °C | 15.4 °C | 1105.65 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| 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 |