| 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 |
| 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: | Dfa - Humid Continental Hot Summers |
| Ecoregion: | 53b - Kettle Moraines |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 53076 - Richfield, WI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 9 | 14 | 24 | 34 | 45 | 54 | 59 | 58 | 49 | 39 | 27 | 15 | 35 |
| Avg Max Temp (°F) | 25 | 30 | 41 | 54 | 67 | 77 | 81 | 78 | 71 | 59 | 43 | 30 | 55 |
| Avg Precip (In.) | 1.36 | 1.18 | 2.04 | 3.24 | 3.04 | 3.8 | 3.97 | 4.24 | 3.53 | 2.51 | 2.51 | 1.71 | 33.12 |