Franklin, Maryland has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 5.1 °C (low) to 17.5 °C (high). Annual precipitation averages 1067.3 Millimeters. Franklin is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.5 °C | 3.9 °C | 73.15 mm |
| February | -4.9 °C | 5.9 °C | 73.66 mm |
| March | -1.3 °C | 10.7 °C | 98.55 mm |
| April | 3.7 °C | 18.4 °C | 92.46 mm |
| May | 8.9 °C | 23.2 °C | 112.27 mm |
| June | 13.9 °C | 27.4 °C | 106.93 mm |
| July | 16.3 °C | 29.7 °C | 103.89 mm |
| August | 15.4 °C | 29 °C | 92.2 mm |
| September | 11.6 °C | 25.4 °C | 99.06 mm |
| October | 5.6 °C | 18.8 °C | 74.93 mm |
| November | 0.2 °C | 11.8 °C | 64.01 mm |
| December | -3.3 °C | 6 °C | 76.2 mm |
| Annual | 5.1 °C | 17.5 °C | 1067.31 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |