| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F | |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°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: | 52b - Paleozoic Plateau/Coulee Section | |
| Current Drought Status: | Exceptional Drought | |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 61036 - Galena, IL | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 9 | 14 | 25 | 36 | 48 | 58 | 62 | 60 | 51 | 39 | 27 | 15 | 37 |
| Avg Max Temp (°F) | 26 | 32 | 44 | 59 | 71 | 80 | 84 | 82 | 74 | 62 | 45 | 31 | 57 |
| Avg Precip (In.) | 1.27 | 1.43 | 2.44 | 3.47 | 3.97 | 4.62 | 3.81 | 4.32 | 3.76 | 2.37 | 2.72 | 1.82 | 36 |