Nelson, Wisconsin has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.6 °C (low) to 13.4 °C (high). Annual precipitation averages 906 Millimeters. Nelson 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.5 °C | -3.8 °C | 25.91 mm |
| February | -11.6 °C | -1.1 °C | 27.18 mm |
| March | -4.8 °C | 5.7 °C | 48.01 mm |
| April | 2.2 °C | 13.9 °C | 87.12 mm |
| May | 8.8 °C | 20.8 °C | 117.09 mm |
| June | 14.6 °C | 26.1 °C | 133.35 mm |
| July | 16.8 °C | 28.2 °C | 109.73 mm |
| August | 15.7 °C | 27.1 °C | 118.62 mm |
| September | 11.2 °C | 23 °C | 96.77 mm |
| October | 4.3 °C | 15.3 °C | 64.26 mm |
| November | -2.7 °C | 6.4 °C | 45.72 mm |
| December | -9.3 °C | -0.9 °C | 32.26 mm |
| Annual | 2.6 °C | 13.4 °C | 906.02 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 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 |