Lancaster, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -2 °C (low) to 9.2 °C (high). Annual precipitation averages 598.7 Millimeters. Lancaster is located in USDA Plant Hardiness Zone 3b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -20.5 °C | -10.7 °C | 17.27 mm |
| February | -18.7 °C | -7.9 °C | 13.97 mm |
| March | -10.6 °C | -0.4 °C | 20.32 mm |
| April | -1.6 °C | 10 °C | 28.19 mm |
| May | 5.4 °C | 18.2 °C | 87.38 mm |
| June | 11.7 °C | 23.4 °C | 107.19 mm |
| July | 13.7 °C | 25.9 °C | 94.74 mm |
| August | 12 °C | 25.6 °C | 72.14 mm |
| September | 7.2 °C | 20.6 °C | 63.5 mm |
| October | 0.6 °C | 11.4 °C | 46.99 mm |
| November | -7.6 °C | 1.1 °C | 26.42 mm |
| December | -15.8 °C | -7.1 °C | 20.57 mm |
| Annual | -2 °C | 9.2 °C | 598.68 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 3b : -37.2°C to -34.4°C |
| Plant Hardiness Zone - 2012 | Zone 3b : -37.2°C to -34.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |