Hayward, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.9 °C (low) to 12.4 °C (high). Annual precipitation averages 900.2 Millimeters. Hayward 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 | -14.4 °C | -5.2 °C | 24.13 mm |
| February | -12.3 °C | -2.7 °C | 24.38 mm |
| March | -5.4 °C | 4.2 °C | 49.53 mm |
| April | 1.5 °C | 12.8 °C | 88.9 mm |
| May | 8.4 °C | 19.8 °C | 121.16 mm |
| June | 14.6 °C | 25.4 °C | 134.11 mm |
| July | 16.5 °C | 27.3 °C | 121.92 mm |
| August | 14.9 °C | 26.1 °C | 107.44 mm |
| September | 10.2 °C | 22.6 °C | 93.98 mm |
| October | 3.1 °C | 14.9 °C | 63.25 mm |
| November | -3.7 °C | 5.8 °C | 39.37 mm |
| December | -10.4 °C | -2.1 °C | 32 mm |
| Annual | 1.9 °C | 12.4 °C | 900.17 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 | Dfb - Humid Continental Mild Summer, Wet All Year |