| 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: | Apr. 21 - Apr. 30 | |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers | |
| Ecoregion: | 72i - Western Dissected Illinoian Till Plain | |
| Current Drought Status: | Abnormally Dry | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 61401 - Galesburg, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 13 | 19 | 29 | 40 | 51 | 61 | 65 | 63 | 54 | 43 | 31 | 19 | 41 |
| Avg Max Temp (°F) | 29 | 35 | 48 | 61 | 73 | 82 | 85 | 83 | 75 | 63 | 47 | 34 | 60 |
| Avg Precip (In.) | 1.43 | 1.52 | 2.83 | 3.78 | 4 | 4.17 | 4.28 | 3.97 | 3.48 | 2.59 | 2.71 | 2.25 | 37.02 |