Morristown, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1.8 °C (low) to 12.6 °C (high). Annual precipitation averages 860.6 Millimeters. Morristown is located in USDA Plant Hardiness Zone 4b. 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 | -14.7 °C | -5 °C | 21.59 mm |
| February | -12.6 °C | -2.4 °C | 24.64 mm |
| March | -5.6 °C | 4.5 °C | 45.21 mm |
| April | 1.3 °C | 13.2 °C | 76.2 mm |
| May | 8.3 °C | 20.1 °C | 109.22 mm |
| June | 14.4 °C | 25.7 °C | 129.29 mm |
| July | 16.3 °C | 27.6 °C | 114.55 mm |
| August | 14.9 °C | 26.3 °C | 118.36 mm |
| September | 10.2 °C | 22.8 °C | 88.39 mm |
| October | 3 °C | 14.9 °C | 62.48 mm |
| November | -3.9 °C | 5.7 °C | 40.39 mm |
| December | -10.6 °C | -1.9 °C | 30.23 mm |
| Annual | 1.8 °C | 12.6 °C | 860.55 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 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |