New Underwood, South Dakota has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 34.7 °F (low) to 60 °F (high). Annual precipitation averages 17.2 Inches. New Underwood is located in USDA Plant Hardiness Zone 5a. 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 | 12.3 °F | 35.2 °F | 0.32 in. |
| February | 14.5 °F | 37.9 °F | 0.41 in. |
| March | 23.3 °F | 48.2 °F | 0.87 in. |
| April | 32.2 °F | 57.2 °F | 1.87 in. |
| May | 43.2 °F | 67.2 °F | 3.48 in. |
| June | 53.3 °F | 78.3 °F | 3.03 in. |
| July | 59.7 °F | 86.8 °F | 2.13 in. |
| August | 57.8 °F | 86.3 °F | 1.64 in. |
| September | 47.8 °F | 77.0 °F | 1.22 in. |
| October | 34.9 °F | 61.6 °F | 1.48 in. |
| November | 23.1 °F | 47.8 °F | 0.42 in. |
| December | 14.3 °F | 36.8 °F | 0.32 in. |
| Annual | 34.7 °F | 60 °F | 17.19 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 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |