Hatfield, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.4 °C (low) to 13.1 °C (high). Annual precipitation averages 905.5 Millimeters. Hatfield is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15 °C | -3.9 °C | 30.23 mm |
| February | -13.3 °C | -1.1 °C | 28.96 mm |
| March | -6.9 °C | 5.6 °C | 45.72 mm |
| April | -0.2 °C | 13.7 °C | 87.12 mm |
| May | 6.3 °C | 20.6 °C | 113.28 mm |
| June | 11.9 °C | 25.6 °C | 129.54 mm |
| July | 14.1 °C | 27.7 °C | 104.14 mm |
| August | 13 °C | 26.6 °C | 109.22 mm |
| September | 8.3 °C | 22.6 °C | 93.98 mm |
| October | 1.8 °C | 15.2 °C | 75.18 mm |
| November | -4.5 °C | 6.1 °C | 49.02 mm |
| December | -10.9 °C | -1.1 °C | 39.12 mm |
| Annual | 0.4 °C | 13.1 °C | 905.51 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |