Franklin, Pennsylvania has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.6 °C (low) to 15.4 °C (high). Annual precipitation averages 1189 Millimeters. Franklin 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 | -6.9 °C | 2.2 °C | 90.68 mm |
| February | -6.2 °C | 3.8 °C | 83.57 mm |
| March | -2.4 °C | 8.6 °C | 102.36 mm |
| April | 3.5 °C | 16.6 °C | 109.22 mm |
| May | 9.1 °C | 22 °C | 109.22 mm |
| June | 13.7 °C | 26.2 °C | 118.11 mm |
| July | 15.9 °C | 28.4 °C | 115.06 mm |
| August | 15.1 °C | 27.6 °C | 112.01 mm |
| September | 11.4 °C | 24.1 °C | 111.25 mm |
| October | 5.2 °C | 17.5 °C | 90.42 mm |
| November | 0 °C | 10.5 °C | 89.92 mm |
| December | -3.8 °C | 4.6 °C | 98.81 mm |
| Annual | 4.6 °C | 16 °C | 1230.63 mm |
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.9 °C | 1.3 °C | 85.6 mm |
| February | -7.8 °C | 2.8 °C | 67.06 mm |
| March | -3.8 °C | 7.8 °C | 89.66 mm |
| April | 1.7 °C | 15.4 °C | 106.43 mm |
| May | 7.7 °C | 21.8 °C | 99.57 mm |
| June | 12.9 °C | 26.1 °C | 129.79 mm |
| July | 15.2 °C | 28.2 °C | 134.11 mm |
| August | 14.4 °C | 27.4 °C | 105.66 mm |
| September | 10.7 °C | 23.7 °C | 100.33 mm |
| October | 4.7 °C | 16.9 °C | 95.76 mm |
| November | -0.4 °C | 9.7 °C | 86.36 mm |
| December | -4.6 °C | 3.8 °C | 88.65 mm |
| Annual | 3.6 °C | 15.4 °C | 1188.98 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |
| 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 |