Underwood, Minnesota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 32 °F (low) to 51.4 °F (high). Annual precipitation averages 26 Inches. Underwood is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 0.1 °F | 18.3 °F | 0.67 in. |
| February | 3.4 °F | 23.1 °F | 0.63 in. |
| March | 17.0 °F | 36.2 °F | 1.09 in. |
| April | 31.2 °F | 52.4 °F | 2.0 in. |
| May | 44.7 °F | 65.8 °F | 3.33 in. |
| June | 55.6 °F | 75.3 °F | 4.31 in. |
| July | 60.1 °F | 79.8 °F | 3.79 in. |
| August | 57.5 °F | 78.2 °F | 3.14 in. |
| September | 49.0 °F | 70.5 °F | 2.86 in. |
| October | 35.6 °F | 55.0 °F | 2.5 in. |
| November | 21.8 °F | 37.7 °F | 0.92 in. |
| December | 8.1 °F | 24.1 °F | 0.76 in. |
| Annual | 32 °F | 51.4 °F | 26 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |