South Fork, Pennsylvania has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.8 °C (low) to 15.3 °C (high). Annual precipitation averages 1203.7 Millimeters. South Fork 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 | -7.5 °C | 1.6 °C | 89.15 mm |
| February | -6.8 °C | 3.2 °C | 79.76 mm |
| March | -3.1 °C | 7.9 °C | 100.08 mm |
| April | 2.7 °C | 15.8 °C | 102.36 mm |
| May | 8.3 °C | 21.2 °C | 111 mm |
| June | 13 °C | 25.4 °C | 116.84 mm |
| July | 15.2 °C | 27.6 °C | 115.57 mm |
| August | 14.3 °C | 26.8 °C | 110.74 mm |
| September | 10.7 °C | 23.3 °C | 106.17 mm |
| October | 4.6 °C | 16.7 °C | 89.92 mm |
| November | -0.7 °C | 9.8 °C | 88.65 mm |
| December | -4.6 °C | 3.9 °C | 93.47 mm |
| Annual | 3.8 °C | 15.3 °C | 1203.71 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 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |