Lemmon, South Dakota has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -0.2 °C (low) to 13.6 °C (high). Annual precipitation averages 446.5 Millimeters. Lemmon 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.8 °C | -2.5 °C | 7.62 mm |
| February | -12.1 °C | -0.3 °C | 10.92 mm |
| March | -7 °C | 5.9 °C | 20.07 mm |
| April | -1.3 °C | 13.3 °C | 38.1 mm |
| May | 5.2 °C | 19.4 °C | 68.83 mm |
| June | 10.8 °C | 24.9 °C | 76.45 mm |
| July | 13.8 °C | 29.5 °C | 72.14 mm |
| August | 12.6 °C | 28.8 °C | 49.53 mm |
| September | 7.3 °C | 24.1 °C | 37.59 mm |
| October | 0.3 °C | 14.9 °C | 38.86 mm |
| November | -6.7 °C | 6 °C | 15.24 mm |
| December | -12 °C | -0.6 °C | 11.18 mm |
| Annual | -0.2 °C | 13.6 °C | 446.53 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |