Lynn, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5 °C (low) to 15.7 °C (high). Annual precipitation averages 1070.6 Millimeters. Lynn is located in USDA Plant Hardiness Zone 6a. 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 | -7.8 °C | 0.9 °C | 74.42 mm |
| February | -6.5 °C | 3 °C | 58.17 mm |
| March | -1.4 °C | 8.9 °C | 83.82 mm |
| April | 4.3 °C | 16.1 °C | 108.2 mm |
| May | 10.5 °C | 21.8 °C | 115.32 mm |
| June | 15.7 °C | 26.5 °C | 121.67 mm |
| July | 16.7 °C | 28.1 °C | 106.43 mm |
| August | 15.8 °C | 27.4 °C | 87.38 mm |
| September | 11.8 °C | 24.4 °C | 79.76 mm |
| October | 5.9 °C | 17.6 °C | 78.49 mm |
| November | 0.1 °C | 10.1 °C | 83.31 mm |
| December | -4.8 °C | 3.4 °C | 73.66 mm |
| Annual | 5 °C | 15.7 °C | 1070.63 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 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 | Dfa - Humid Continental Hot Summers With Year Around Precipitation |