Ferney, South Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 32.5 °F (low) to 55 °F (high). Annual precipitation averages 23 Inches. Ferney is located in USDA Plant Hardiness Zone 4a. 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 | 2.4 °F | 22.0 °F | 0.56 in. |
| February | 6.6 °F | 27.4 °F | 0.63 in. |
| March | 19.2 °F | 40.2 °F | 1.0 in. |
| April | 31.7 °F | 55.9 °F | 2.13 in. |
| May | 44.7 °F | 68.6 °F | 3.15 in. |
| June | 55.7 °F | 78.3 °F | 3.9 in. |
| July | 60.3 °F | 83.5 °F | 3.53 in. |
| August | 57.6 °F | 82.2 °F | 2.32 in. |
| September | 48.0 °F | 74.0 °F | 2.21 in. |
| October | 34.3 °F | 58.8 °F | 2.17 in. |
| November | 20.6 °F | 41.6 °F | 0.77 in. |
| December | 8.7 °F | 27.5 °F | 0.65 in. |
| Annual | 32.5 °F | 55 °F | 23.02 in. |
| 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 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |