Sherman, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 34.7 °F (low) to 55.4 °F (high). Annual precipitation averages 28.7 Inches. Sherman 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 | 6.1 °F | 24.2 °F | 0.67 in. |
| February | 10.2 °F | 28.9 °F | 0.85 in. |
| March | 21.9 °F | 41.3 °F | 1.44 in. |
| April | 33.5 °F | 56.1 °F | 2.87 in. |
| May | 46.3 °F | 68.2 °F | 3.75 in. |
| June | 58.0 °F | 78.4 °F | 4.45 in. |
| July | 61.4 °F | 82.5 °F | 3.57 in. |
| August | 58.5 °F | 80.3 °F | 3.45 in. |
| September | 49.5 °F | 73.6 °F | 3.22 in. |
| October | 36.3 °F | 59.5 °F | 2.26 in. |
| November | 23.0 °F | 43.0 °F | 1.23 in. |
| December | 11.8 °F | 28.8 °F | 0.97 in. |
| Annual | 34.7 °F | 55.4 °F | 28.73 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 | Extreme Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |