Franklin, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.2 °C (low) to 17.2 °C (high). Annual precipitation averages 1151.4 Millimeters. Franklin is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.5 °C | 2.3 °C | 80.52 mm |
| February | -5 °C | 4.8 °C | 65.28 mm |
| March | -0.3 °C | 10.8 °C | 90.93 mm |
| April | 5.7 °C | 17.7 °C | 122.68 mm |
| May | 11.6 °C | 23.1 °C | 129.79 mm |
| June | 16.7 °C | 27.8 °C | 131.83 mm |
| July | 18.4 °C | 29.3 °C | 112.27 mm |
| August | 17.3 °C | 28.9 °C | 82.3 mm |
| September | 13.1 °C | 25.9 °C | 83.31 mm |
| October | 6.6 °C | 19.1 °C | 81.53 mm |
| November | 0.8 °C | 11.3 °C | 86.87 mm |
| December | -3.6 °C | 4.9 °C | 84.07 mm |
| Annual | 6.2 °C | 17.2 °C | 1151.38 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 |