| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F | |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F | |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F | |
| Average First Frost Date: | Oct. 11 - Oct. 20 | |
| Average Last Frost Date: | May 11 - May 20 | |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers | |
| Ecoregion: | 52b - Paleozoic Plateau/Coulee Section | |
| Current Drought Status: | Abnormally Dry | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 61041 - Hanover, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 9 | 14 | 26 | 37 | 48 | 58 | 62 | 60 | 51 | 39 | 28 | 16 | 37 |
| Avg Max Temp (°F) | 27 | 33 | 45 | 59 | 71 | 81 | 84 | 82 | 74 | 62 | 45 | 32 | 58 |
| Avg Precip (In.) | 1.21 | 1.31 | 2.34 | 3.41 | 3.84 | 4.55 | 3.54 | 4.41 | 3.57 | 2.53 | 2.61 | 1.67 | 34.99 |