| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F 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: | 54a - Illinois/Indiana Prairies |
| Heat Zone Days: | 15 - 30 days Over 86°F |
Annual Climate Data for ZIP Code 61561 - Roanoke, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 14 | 19 | 29 | 39 | 50 | 59 | 63 | 61 | 53 | 42 | 31 | 20 | 40 |
| Avg Max Temp (°F) | 31 | 37 | 49 | 62 | 74 | 83 | 86 | 84 | 78 | 66 | 49 | 36 | 61 |
| Avg Precip (In.) | 1.66 | 1.69 | 2.96 | 3.59 | 4.17 | 4.05 | 3.91 | 3.48 | 3.34 | 2.78 | 3.13 | 2.46 | 37.22 |