Spencer, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.8 °C (low) to 11.6 °C (high). Annual precipitation averages 831.1 Millimeters. Spencer is located in USDA Plant Hardiness Zone 4b. 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 | -15 °C | -5.3 °C | 26.92 mm |
| February | -13.7 °C | -2.8 °C | 25.15 mm |
| March | -7 °C | 4 °C | 42.16 mm |
| April | 0.2 °C | 11.9 °C | 76.2 mm |
| May | 7.2 °C | 18.9 °C | 95.5 mm |
| June | 12.6 °C | 23.9 °C | 120.4 mm |
| July | 14.8 °C | 26.5 °C | 93.47 mm |
| August | 13.6 °C | 25.3 °C | 100.58 mm |
| September | 9.1 °C | 21.1 °C | 94.49 mm |
| October | 2.3 °C | 13.6 °C | 73.66 mm |
| November | -4 °C | 4.9 °C | 46.74 mm |
| December | -10.7 °C | -2.3 °C | 35.81 mm |
| Annual | 0.8 °C | 11.6 °C | 831.08 mm |
| 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 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |