| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 4b: -25°F to -20°F |
| 1990 Hardiness Zone: | Zone 4b: -25F to -20F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 52b - Paleozoic Plateau/Coulee Section |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 54634 - Hillsboro, WI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 3 | 9 | 21 | 33 | 44 | 54 | 59 | 56 | 47 | 36 | 24 | 10 | 33 |
| Avg Max Temp (°F) | 24 | 30 | 42 | 56 | 69 | 78 | 82 | 80 | 71 | 60 | 43 | 29 | 55 |
| Avg Precip (In.) | 1.03 | 1.02 | 2 | 3.39 | 3.59 | 4.1 | 4.18 | 4.34 | 3.78 | 2.37 | 2.24 | 1.14 | 33.17 |