Edgemont, South Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.7 °C (low) to 16.9 °C (high). Annual precipitation averages 416.1 Millimeters. Edgemont is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.8 °C | 2.7 °C | 9.65 mm |
| February | -9.8 °C | 4.9 °C | 11.94 mm |
| March | -5 °C | 10.9 °C | 22.61 mm |
| April | -0.4 °C | 15.7 °C | 46.74 mm |
| May | 5.6 °C | 20.8 °C | 69.6 mm |
| June | 11.1 °C | 27.2 °C | 69.09 mm |
| July | 14.8 °C | 32.2 °C | 58.17 mm |
| August | 13.3 °C | 31.6 °C | 37.08 mm |
| September | 7.6 °C | 26.3 °C | 32.51 mm |
| October | 0.4 °C | 17.4 °C | 32.51 mm |
| November | -6.3 °C | 9.4 °C | 14.48 mm |
| December | -11.2 °C | 3.3 °C | 11.68 mm |
| Annual | 0.7 °C | 16.9 °C | 416.06 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| 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 | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |