| 2023 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°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: | 53c - Southeastern Wisconsin Savannah and Till Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 53551 - Lake Mills, WI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 8 | 13 | 24 | 36 | 47 | 57 | 62 | 60 | 51 | 40 | 28 | 16 | 37 |
| Avg Max Temp (°F) | 26 | 31 | 43 | 57 | 70 | 79 | 83 | 80 | 72 | 61 | 44 | 31 | 56 |
| Avg Precip (In.) | 1.39 | 1.23 | 2.22 | 3.34 | 3.32 | 3.95 | 4.1 | 4.46 | 3.56 | 2.44 | 2.4 | 1.67 | 34.1 |