Twin Brooks, South Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 33 °F (low) to 53.9 °F (high). Annual precipitation averages 25.1 Inches. Twin Brooks is located in USDA Plant Hardiness Zone 4b. 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 | 3.1 °F | 21.6 °F | 0.66 in. |
| February | 6.5 °F | 26.0 °F | 0.67 in. |
| March | 19.0 °F | 38.3 °F | 1.19 in. |
| April | 31.9 °F | 54.2 °F | 2.5 in. |
| May | 45.3 °F | 67.6 °F | 2.94 in. |
| June | 56.3 °F | 77.6 °F | 3.88 in. |
| July | 60.3 °F | 82.1 °F | 3.87 in. |
| August | 57.7 °F | 80.3 °F | 2.93 in. |
| September | 48.5 °F | 72.6 °F | 2.41 in. |
| October | 35.3 °F | 57.6 °F | 2.33 in. |
| November | 22.3 °F | 41.2 °F | 0.94 in. |
| December | 10.0 °F | 27.2 °F | 0.77 in. |
| Annual | 33 °F | 53.9 °F | 25.09 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 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |