Spencer, 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 57.1 °F (high). Annual precipitation averages 26.3 Inches. Spencer 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 | 25.9 °F | 0.53 in. |
| February | 11.4 °F | 31.2 °F | 0.76 in. |
| March | 22.2 °F | 43.2 °F | 1.24 in. |
| April | 34.0 °F | 57.6 °F | 2.92 in. |
| May | 46.7 °F | 69.7 °F | 3.74 in. |
| June | 58.0 °F | 79.8 °F | 3.99 in. |
| July | 62.0 °F | 84.9 °F | 3.21 in. |
| August | 59.6 °F | 82.5 °F | 3.1 in. |
| September | 50.6 °F | 75.3 °F | 2.97 in. |
| October | 36.6 °F | 60.9 °F | 2.23 in. |
| November | 23.0 °F | 44.0 °F | 0.95 in. |
| December | 12.1 °F | 30.3 °F | 0.69 in. |
| Annual | 35.3 °F | 57.1 °F | 26.33 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 |