Crystal Lawns, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.7 °F (low) to 60.2 °F (high). Annual precipitation averages 40.1 Inches. Crystal Lawns is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 15.9 °F | 31.6 °F | 2.13 in. |
| February | 18.7 °F | 35.5 °F | 1.96 in. |
| March | 28.4 °F | 47.6 °F | 2.52 in. |
| April | 38.9 °F | 60.7 °F | 3.97 in. |
| May | 49.9 °F | 71.6 °F | 4.82 in. |
| June | 60.0 °F | 81.0 °F | 4.72 in. |
| July | 63.8 °F | 84.5 °F | 4.28 in. |
| August | 62.3 °F | 82.7 °F | 4.22 in. |
| September | 54.4 °F | 77.0 °F | 3.38 in. |
| October | 42.3 °F | 63.9 °F | 3.41 in. |
| November | 31.8 °F | 49.2 °F | 2.47 in. |
| December | 21.8 °F | 36.8 °F | 2.2 in. |
| Annual | 40.7 °F | 60.2 °F | 40.08 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 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 | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |