Roswell, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 1.6 °C (low) to 13.8 °C (high). Annual precipitation averages 623.3 Millimeters. Roswell 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 | -14.1 °C | -3.7 °C | 12.95 mm |
| February | -11.7 °C | -0.7 °C | 17.02 mm |
| March | -5.7 °C | 6.1 °C | 30.23 mm |
| April | 0.9 °C | 14.2 °C | 69.34 mm |
| May | 7.9 °C | 20.8 °C | 91.44 mm |
| June | 14.1 °C | 26.3 °C | 96.01 mm |
| July | 16.4 °C | 29.3 °C | 72.9 mm |
| August | 15.2 °C | 28.1 °C | 71.63 mm |
| September | 10.3 °C | 23.8 °C | 70.61 mm |
| October | 2.5 °C | 15.8 °C | 54.1 mm |
| November | -5.1 °C | 6.5 °C | 22.35 mm |
| December | -11.3 °C | -1.1 °C | 14.73 mm |
| Annual | 1.6 °C | 13.8 °C | 623.31 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |