Elkton, South Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 1 °C (low) to 12.2 °C (high). Annual precipitation averages 692.9 Millimeters. Elkton 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 | -15 °C | -5.2 °C | 16 mm |
| February | -12.9 °C | -2.6 °C | 18.8 mm |
| March | -6.4 °C | 4.1 °C | 35.05 mm |
| April | 0.3 °C | 12.3 °C | 67.06 mm |
| May | 7.6 °C | 19.4 °C | 94.23 mm |
| June | 13.7 °C | 24.9 °C | 111.76 mm |
| July | 15.9 °C | 27.5 °C | 87.63 mm |
| August | 14.4 °C | 26.2 °C | 80.26 mm |
| September | 9.6 °C | 22.3 °C | 78.74 mm |
| October | 2.1 °C | 14.4 °C | 55.12 mm |
| November | -5.3 °C | 5.3 °C | 25.91 mm |
| December | -11.7 °C | -2.4 °C | 22.35 mm |
| Annual | 1 °C | 12.2 °C | 692.91 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 | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |