Shenandoah, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.7 °C (low) to 15 °C (high). Annual precipitation averages 1303 Millimeters. Shenandoah 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 | -8.2 °C | 1.3 °C | 92.2 mm |
| February | -7.6 °C | 2.8 °C | 72.14 mm |
| March | -3.3 °C | 7.5 °C | 95.76 mm |
| April | 2.6 °C | 14.9 °C | 106.43 mm |
| May | 7.9 °C | 20.8 °C | 115.57 mm |
| June | 12.9 °C | 25.1 °C | 127.51 mm |
| July | 15.4 °C | 27.8 °C | 125.98 mm |
| August | 14.2 °C | 26.8 °C | 113.79 mm |
| September | 10.6 °C | 23.1 °C | 133.35 mm |
| October | 4.6 °C | 16.7 °C | 124.46 mm |
| November | -0.5 °C | 9.7 °C | 93.98 mm |
| December | -4.8 °C | 4 °C | 101.85 mm |
| Annual | 3.7 °C | 15 °C | 1303.02 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |