Argonne, Wisconsin has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.1 °C (low) to 10.6 °C (high). Annual precipitation averages 823.7 Millimeters. Argonne is located in USDA Plant Hardiness Zone 4b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15.9 °C | -5.7 °C | 30.48 mm |
| February | -15.2 °C | -3.1 °C | 26.42 mm |
| March | -9.8 °C | 3.2 °C | 41.4 mm |
| April | -2.5 °C | 10.4 °C | 70.61 mm |
| May | 4.6 °C | 18.1 °C | 89.15 mm |
| June | 10.2 °C | 22.9 °C | 112.52 mm |
| July | 12.5 °C | 25.1 °C | 106.17 mm |
| August | 11.4 °C | 23.9 °C | 85.6 mm |
| September | 7.3 °C | 19.6 °C | 93.47 mm |
| October | 1 °C | 12 °C | 81.28 mm |
| November | -5.2 °C | 3.6 °C | 47.75 mm |
| December | -11.9 °C | -3.1 °C | 38.86 mm |
| Annual | -1.1 °C | 10.6 °C | 823.71 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°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 |