Creve Coeur, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.3 °C (low) to 16.4 °C (high). Annual precipitation averages 980.2 Millimeters. Creve Coeur 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.8 °C | 0.4 °C | 53.59 mm |
| February | -6.8 °C | 3.1 °C | 51.56 mm |
| March | -1.4 °C | 9.9 °C | 65.28 mm |
| April | 4.7 °C | 16.9 °C | 98.04 mm |
| May | 11.1 °C | 22.8 °C | 119.89 mm |
| June | 16.4 °C | 27.8 °C | 115.32 mm |
| July | 18.3 °C | 29.6 °C | 100.84 mm |
| August | 17.2 °C | 28.7 °C | 86.61 mm |
| September | 12.7 °C | 25.6 °C | 87.12 mm |
| October | 6 °C | 18.4 °C | 80.52 mm |
| November | -0.3 °C | 10.3 °C | 68.58 mm |
| December | -5.5 °C | 3.4 °C | 52.83 mm |
| Annual | 5.3 °C | 16.4 °C | 980.18 mm |
| 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 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |