Kildeer, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.9 °F (low) to 58.5 °F (high). Annual precipitation averages 38 Inches. Kildeer is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 15.0 °F | 30.4 °F | 1.95 in. |
| February | 17.8 °F | 34.2 °F | 1.97 in. |
| March | 27.2 °F | 45.4 °F | 2.27 in. |
| April | 37.4 °F | 57.9 °F | 3.79 in. |
| May | 48.3 °F | 69.2 °F | 4.58 in. |
| June | 58.3 °F | 79.3 °F | 4.52 in. |
| July | 63.5 °F | 83.6 °F | 3.8 in. |
| August | 62.1 °F | 81.5 °F | 4.02 in. |
| September | 54.1 °F | 74.7 °F | 3.35 in. |
| October | 42.3 °F | 61.9 °F | 3.25 in. |
| November | 31.1 °F | 47.6 °F | 2.38 in. |
| December | 21.1 °F | 35.7 °F | 2.11 in. |
| Annual | 39.9 °F | 58.5 °F | 37.99 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |