Armour, South Dakota has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 36.5 °F (low) to 59.9 °F (high). Annual precipitation averages 26 Inches. Armour 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 | 9.9 °F | 30.2 °F | 0.63 in. |
| February | 14.0 °F | 35.5 °F | 0.77 in. |
| March | 23.8 °F | 47.2 °F | 1.3 in. |
| April | 34.9 °F | 59.6 °F | 3.0 in. |
| May | 47.0 °F | 71.3 °F | 3.75 in. |
| June | 57.9 °F | 81.4 °F | 3.86 in. |
| July | 62.9 °F | 87.6 °F | 3.1 in. |
| August | 60.6 °F | 85.5 °F | 3.0 in. |
| September | 51.0 °F | 77.8 °F | 2.77 in. |
| October | 37.6 °F | 62.6 °F | 2.17 in. |
| November | 24.5 °F | 46.9 °F | 0.93 in. |
| December | 14.3 °F | 33.6 °F | 0.73 in. |
| Annual | 36.5 °F | 59.9 °F | 26.01 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 5a : -20°F to -15°F |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |