| 2023 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 2012 Hardiness Zone: | Zone 5a: -20°F to -15°F Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 5a: -20F to -15F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | May 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 53b - Kettle Moraines |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 53089 - Sussex, WI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 10 | 15 | 25 | 35 | 46 | 56 | 61 | 59 | 51 | 40 | 28 | 16 | 37 |
| Avg Max Temp (°F) | 26 | 31 | 42 | 55 | 68 | 78 | 82 | 79 | 71 | 60 | 44 | 31 | 56 |
| Avg Precip (In.) | 1.42 | 1.22 | 2.12 | 3.39 | 3.02 | 3.76 | 3.86 | 4.39 | 3.49 | 2.51 | 2.52 | 1.8 | 33.51 |