| 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: | Apr. 21 - Apr. 30 | |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers | |
| Ecoregion: | 72d - Upper Mississippi Alluvial Plain | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | 8 - 14 days Over 86°F |
Annual Climate Data for ZIP Code 61327 - Hennepin, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 13 | 18 | 29 | 39 | 49 | 59 | 63 | 61 | 53 | 41 | 30 | 19 | 39 |
| Avg Max Temp (°F) | 30 | 36 | 48 | 62 | 73 | 83 | 86 | 84 | 77 | 65 | 49 | 35 | 61 |
| Avg Precip (In.) | 1.29 | 1.35 | 2.38 | 3.43 | 3.82 | 4.25 | 3.85 | 4.16 | 3.51 | 2.75 | 2.62 | 2.11 | 35.52 |