Millville, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.3 °F (low) to 55.3 °F (high). Annual precipitation averages 35.4 Inches. Millville 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 6.1 °F | 24.0 °F | 0.97 in. |
| February | 9.4 °F | 28.5 °F | 1.05 in. |
| March | 22.3 °F | 41.1 °F | 1.91 in. |
| April | 34.5 °F | 56.0 °F | 3.36 in. |
| May | 46.7 °F | 68.8 °F | 4.52 in. |
| June | 57.1 °F | 78.5 °F | 5.35 in. |
| July | 61.1 °F | 82.2 °F | 4.24 in. |
| August | 58.7 °F | 80.1 °F | 4.64 in. |
| September | 50.6 °F | 73.1 °F | 3.84 in. |
| October | 37.9 °F | 59.1 °F | 2.47 in. |
| November | 25.7 °F | 42.6 °F | 1.76 in. |
| December | 13.7 °F | 29.4 °F | 1.25 in. |
| Annual | 35.3 °F | 55.3 °F | 35.36 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |