| 2023 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Oct. 11 - Oct. 20 |
| Average Last Frost Date: | May 1 - May 10 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 54f - Valparaiso-Wheaton Morainal Complex |
| Heat Zone Days: | 1 - 7 days Over 86°F |
Annual Climate Data for ZIP Code 60185 - West Chicago, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 12 | 17 | 27 | 37 | 47 | 57 | 62 | 60 | 52 | 41 | 30 | 19 | 38 |
| Avg Max Temp (°F) | 30 | 36 | 47 | 60 | 72 | 81 | 85 | 83 | 76 | 64 | 48 | 35 | 60 |
| Avg Precip (In.) | 1.71 | 1.49 | 2.49 | 3.77 | 3.88 | 4.22 | 4.04 | 4.42 | 3.45 | 2.65 | 3.11 | 2.32 | 37.55 |