| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F |
| 2012 Hardiness Zone: | Zone 5b: -15°F to -10°F |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| 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: | 53d - Lake Michigan Lacustrine Clay Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 53217 - Milwaukee, WI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 12 | 17 | 26 | 36 | 47 | 56 | 62 | 61 | 53 | 42 | 30 | 18 | 38 |
| Avg Max Temp (°F) | 28 | 32 | 42 | 53 | 66 | 76 | 81 | 79 | 72 | 60 | 45 | 33 | 55 |
| Avg Precip (In.) | 1.53 | 1.33 | 2.13 | 3.48 | 2.97 | 3.65 | 3.71 | 4.08 | 3.44 | 2.43 | 2.48 | 1.94 | 33.19 |