Delavan, Minnesota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.1 °C (low) to 13 °C (high). Annual precipitation averages 842 Millimeters. Delavan 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 | -14.3 °C | -4.7 °C | 20.83 mm |
| February | -12.1 °C | -2.2 °C | 22.35 mm |
| March | -5.1 °C | 4.7 °C | 44.7 mm |
| April | 1.7 °C | 13.6 °C | 79.25 mm |
| May | 8.8 °C | 20.7 °C | 111.25 mm |
| June | 14.9 °C | 26.2 °C | 132.08 mm |
| July | 16.7 °C | 28 °C | 108.46 mm |
| August | 15.3 °C | 26.6 °C | 103.63 mm |
| September | 10.6 °C | 23.3 °C | 86.11 mm |
| October | 3.3 °C | 15.6 °C | 66.55 mm |
| November | -3.9 °C | 6 °C | 37.85 mm |
| December | -10.4 °C | -1.7 °C | 28.96 mm |
| Annual | 2.1 °C | 13 °C | 842.02 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 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |