| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°F Zone 6b: -5°F to 0°F 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 11 - May 20 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 56d - Michigan Lake Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 49419 - Hamilton, MI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 16 | 18 | 25 | 35 | 45 | 55 | 59 | 58 | 51 | 40 | 32 | 22 | 38 |
| Avg Max Temp (°F) | 30 | 33 | 44 | 56 | 68 | 77 | 82 | 80 | 72 | 60 | 47 | 35 | 57 |
| Avg Precip (In.) | 2.5 | 1.66 | 2.48 | 3.35 | 3.44 | 3.73 | 3.51 | 3.8 | 4.06 | 2.98 | 3.43 | 3.04 | 37.95 |