Farmer, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 35.3 °F (low) to 57.4 °F (high). Annual precipitation averages 25.9 Inches. Farmer 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 | 7.1 °F | 26.1 °F | 0.51 in. |
| February | 11.5 °F | 31.7 °F | 0.75 in. |
| March | 22.2 °F | 43.7 °F | 1.23 in. |
| April | 34.1 °F | 58.1 °F | 2.89 in. |
| May | 46.7 °F | 70.0 °F | 3.68 in. |
| June | 57.9 °F | 80.0 °F | 3.97 in. |
| July | 62.0 °F | 85.2 °F | 3.19 in. |
| August | 59.6 °F | 83.0 °F | 3.0 in. |
| September | 50.8 °F | 75.7 °F | 2.89 in. |
| October | 36.7 °F | 61.2 °F | 2.15 in. |
| November | 23.1 °F | 44.2 °F | 0.95 in. |
| December | 12.1 °F | 30.4 °F | 0.69 in. |
| Annual | 35.3 °F | 57.4 °F | 25.9 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 4b : -25°F to -20°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |