Mason, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31.1 °F (low) to 51.7 °F (high). Annual precipitation averages 32.9 Inches. Mason is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.5 °F | 21.7 °F | 1.25 in. |
| February | 5.9 °F | 26.6 °F | 1.06 in. |
| March | 16.7 °F | 37.8 °F | 1.64 in. |
| April | 29.0 °F | 50.1 °F | 2.86 in. |
| May | 40.0 °F | 64.1 °F | 3.74 in. |
| June | 50.3 °F | 73.5 °F | 4.07 in. |
| July | 55.8 °F | 78.4 °F | 4.36 in. |
| August | 54.2 °F | 76.9 °F | 3.64 in. |
| September | 47.0 °F | 69.2 °F | 3.57 in. |
| October | 35.2 °F | 54.8 °F | 3.27 in. |
| November | 24.0 °F | 39.9 °F | 1.87 in. |
| December | 11.7 °F | 26.9 °F | 1.55 in. |
| Annual | 31.1 °F | 51.7 °F | 32.88 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 3b : -35°F to -30°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |