Loomis, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 35.6 °F (low) to 57.7 °F (high). Annual precipitation averages 24.8 Inches. Loomis 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 | 7.6 °F | 26.9 °F | 0.56 in. |
| February | 11.6 °F | 32.3 °F | 0.77 in. |
| March | 22.3 °F | 44.0 °F | 1.22 in. |
| April | 34.3 °F | 57.7 °F | 2.95 in. |
| May | 47.0 °F | 69.8 °F | 3.44 in. |
| June | 58.2 °F | 79.9 °F | 3.78 in. |
| July | 62.5 °F | 85.5 °F | 2.91 in. |
| August | 60.0 °F | 83.4 °F | 2.93 in. |
| September | 50.7 °F | 75.9 °F | 2.55 in. |
| October | 36.6 °F | 61.2 °F | 2.03 in. |
| November | 23.4 °F | 44.8 °F | 0.89 in. |
| December | 12.5 °F | 31.2 °F | 0.72 in. |
| Annual | 35.6 °F | 57.7 °F | 24.75 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 |