| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°F 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 21 - May 31 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 50ac - Onaway Moraines |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 48740 - Harrisville, MI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 11 | 11 | 20 | 32 | 43 | 52 | 57 | 56 | 48 | 38 | 29 | 19 | 35 |
| Avg Max Temp (°F) | 27 | 29 | 38 | 50 | 63 | 73 | 78 | 76 | 68 | 56 | 43 | 33 | 53 |
| Avg Precip (In.) | 1.81 | 1.3 | 2.02 | 2.48 | 2.71 | 2.99 | 2.97 | 3.59 | 3.3 | 2.47 | 2.31 | 1.94 | 29.89 |