Fairmont, Minnesota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.3 °C (low) to 12.9 °C (high). Annual precipitation averages 826.3 Millimeters. Fairmont is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.9 °C | -4.7 °C | 21.59 mm |
| February | -11.7 °C | -2.3 °C | 24.13 mm |
| March | -4.8 °C | 4.7 °C | 46.23 mm |
| April | 1.8 °C | 13.4 °C | 83.82 mm |
| May | 9 °C | 20.5 °C | 113.28 mm |
| June | 15.1 °C | 26.1 °C | 123.19 mm |
| July | 17 °C | 27.9 °C | 101.6 mm |
| August | 15.4 °C | 26.4 °C | 93.73 mm |
| September | 10.7 °C | 23.4 °C | 85.09 mm |
| October | 3.6 °C | 15.3 °C | 64.01 mm |
| November | -3.8 °C | 6.1 °C | 37.85 mm |
| December | -10.3 °C | -1.7 °C | 31.75 mm |
| Annual | 2.3 °C | 12.9 °C | 826.27 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |