Calumet City, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.9 °F (low) to 59.7 °F (high). Annual precipitation averages 39.8 Inches. Calumet City is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.7 °F | 32.9 °F | 2.26 in. |
| February | 21.3 °F | 36.4 °F | 2.12 in. |
| March | 30.2 °F | 46.6 °F | 2.37 in. |
| April | 40.2 °F | 58.7 °F | 3.67 in. |
| May | 50.7 °F | 69.5 °F | 4.24 in. |
| June | 60.7 °F | 79.4 °F | 4.61 in. |
| July | 66.1 °F | 83.5 °F | 4.32 in. |
| August | 64.8 °F | 81.9 °F | 4.11 in. |
| September | 57.3 °F | 76.0 °F | 3.27 in. |
| October | 45.5 °F | 63.4 °F | 3.63 in. |
| November | 34.4 °F | 49.7 °F | 2.83 in. |
| December | 24.5 °F | 37.9 °F | 2.33 in. |
| Annual | 42.9 °F | 59.7 °F | 39.76 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |