| 2023 Hardiness Zone: | Zone 5b: -15°F to -10°F | |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F | |
| 1990 Hardiness Zone: | Zone 4b: -25F to -20F | |
| 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: | 54g - Rock River Hills | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 61101 - Rockford, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 10 | 16 | 26 | 36 | 47 | 57 | 62 | 60 | 51 | 39 | 28 | 16 | 37 |
| Avg Max Temp (°F) | 27 | 32 | 45 | 59 | 71 | 80 | 83 | 81 | 74 | 62 | 45 | 32 | 58 |
| Avg Precip (In.) | 1.39 | 1.33 | 2.33 | 3.59 | 3.84 | 4.63 | 4.01 | 4.29 | 3.48 | 2.58 | 2.67 | 1.95 | 36.08 |