Richfield, Wisconsin has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.5 °C (low) to 13.1 °C (high). Annual precipitation averages 908.8 Millimeters. Richfield is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.6 °C | -2.8 °C | 46.48 mm |
| February | -9.9 °C | -0.8 °C | 43.43 mm |
| March | -4.7 °C | 5.5 °C | 53.34 mm |
| April | 1.3 °C | 12.7 °C | 97.03 mm |
| May | 7.2 °C | 19.3 °C | 101.6 mm |
| June | 12.6 °C | 24.6 °C | 110.74 mm |
| July | 15.6 °C | 27.3 °C | 102.11 mm |
| August | 14.6 °C | 26.2 °C | 93.98 mm |
| September | 10.2 °C | 22.3 °C | 80.26 mm |
| October | 4.1 °C | 15.1 °C | 72.14 mm |
| November | -2.1 °C | 7.1 °C | 55.37 mm |
| December | -7.8 °C | 0.3 °C | 52.32 mm |
| Annual | 2.5 °C | 13.1 °C | 908.8 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°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 |