Whittlesey, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.6 °C (low) to 10.9 °C (high). Annual precipitation averages 845.1 Millimeters. Whittlesey is located in USDA Plant Hardiness Zone 4a. 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 | -16.3 °C | -6.1 °C | 28.19 mm |
| February | -15.3 °C | -3.3 °C | 26.42 mm |
| March | -8.8 °C | 3.2 °C | 42.16 mm |
| April | -1.4 °C | 10.9 °C | 74.17 mm |
| May | 5.8 °C | 18.4 °C | 93.73 mm |
| June | 11.3 °C | 23.4 °C | 119.13 mm |
| July | 13.4 °C | 25.8 °C | 96.77 mm |
| August | 12.2 °C | 24.6 °C | 103.12 mm |
| September | 7.9 °C | 20.4 °C | 98.04 mm |
| October | 1.3 °C | 12.6 °C | 78.99 mm |
| November | -4.8 °C | 3.9 °C | 47.5 mm |
| December | -11.9 °C | -3.1 °C | 36.83 mm |
| Annual | -0.6 °C | 10.9 °C | 845.05 mm |
| 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 4a : -34.4°C to -31.7°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |