Byrnedale, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.5 °C (low) to 14.7 °C (high). Annual precipitation averages 1043.7 Millimeters. Byrnedale is located in USDA Plant Hardiness Zone 6a. 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 | -9.1 °C | 0.6 °C | 88.65 mm |
| February | -8.8 °C | 2.2 °C | 67.31 mm |
| March | -4.7 °C | 7.2 °C | 82.3 mm |
| April | 0.8 °C | 14.9 °C | 91.44 mm |
| May | 6.8 °C | 21.2 °C | 102.11 mm |
| June | 11.7 °C | 25.2 °C | 93.98 mm |
| July | 14.1 °C | 27.3 °C | 85.85 mm |
| August | 13.4 °C | 26.5 °C | 83.57 mm |
| September | 9.6 °C | 22.9 °C | 99.57 mm |
| October | 3.3 °C | 16.1 °C | 86.11 mm |
| November | -1.7 °C | 9.1 °C | 81.03 mm |
| December | -5.6 °C | 3.1 °C | 81.79 mm |
| Annual | 2.5 °C | 14.7 °C | 1043.71 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |