| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F |
| 2012 Hardiness Zone: | Zone 6a: -10°F to -5°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: | 56f - Lake Michigan Moraines |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 49010 - Allegan, MI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 15 | 16 | 24 | 34 | 44 | 54 | 58 | 57 | 49 | 39 | 30 | 21 | 37 |
| Avg Max Temp (°F) | 30 | 33 | 44 | 56 | 69 | 78 | 82 | 80 | 72 | 60 | 46 | 34 | 57 |
| Avg Precip (In.) | 2.75 | 1.8 | 2.62 | 3.49 | 3.55 | 3.87 | 3.59 | 3.91 | 4.14 | 3.02 | 3.58 | 3.2 | 39.54 |