Forest City, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 2.2 °C (low) to 13 °C (high). Annual precipitation averages 1161 Millimeters. Forest City 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. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.2 °C | -0.8 °C | 89.66 mm |
| February | -9.7 °C | 0.7 °C | 70.61 mm |
| March | -5.4 °C | 5.3 °C | 79.25 mm |
| April | 0.6 °C | 12.7 °C | 102.11 mm |
| May | 6.8 °C | 19 °C | 113.28 mm |
| June | 12 °C | 23.4 °C | 131.57 mm |
| July | 14.4 °C | 25.8 °C | 108.2 mm |
| August | 13.6 °C | 24.9 °C | 92.46 mm |
| September | 9.6 °C | 21.2 °C | 101.35 mm |
| October | 3.2 °C | 14.4 °C | 108.71 mm |
| November | -1.7 °C | 7.9 °C | 72.9 mm |
| December | -6.3 °C | 1.9 °C | 90.93 mm |
| Annual | 2.2 °C | 13 °C | 1161.03 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| 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 |