| 2023 Hardiness Zone: | Zone 5b: -15°F to -10°F | |
| 2012 Hardiness Zone: | 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: | 53a - Rock River Drift Plain | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 61109 - 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 | 40 | 29 | 16 | 38 |
| Avg Max Temp (°F) | 27 | 33 | 45 | 59 | 71 | 80 | 83 | 81 | 74 | 62 | 46 | 32 | 58 |
| Avg Precip (In.) | 1.41 | 1.34 | 2.38 | 3.6 | 3.94 | 4.73 | 4.05 | 4.27 | 3.46 | 2.57 | 2.68 | 2.02 | 36.46 |