Orviston, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.4 °C (low) to 15.2 °C (high). Annual precipitation averages 1112 Millimeters. Orviston is located in USDA Plant Hardiness Zone 6b. 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 | -8.1 °C | 1.1 °C | 78.49 mm |
| February | -7.6 °C | 2.8 °C | 62.48 mm |
| March | -3.7 °C | 7.7 °C | 86.61 mm |
| April | 2.1 °C | 15.4 °C | 94.74 mm |
| May | 7.9 °C | 21.5 °C | 102.87 mm |
| June | 12.6 °C | 25.7 °C | 104.65 mm |
| July | 14.9 °C | 28.1 °C | 106.43 mm |
| August | 14.1 °C | 27.1 °C | 102.11 mm |
| September | 10.1 °C | 23.3 °C | 110.49 mm |
| October | 4.2 °C | 16.5 °C | 97.79 mm |
| November | -0.9 °C | 9.7 °C | 82.3 mm |
| December | -4.8 °C | 3.5 °C | 83.06 mm |
| Annual | 3.4 °C | 15.2 °C | 1112.02 mm |
| 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 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 |