| 2023 Hardiness Zone: | Zone 6a: -10°F to -5°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 1b: -15F to -10F |
| Average First Frost Date: | Oct. 1 - Oct. 10 |
| Average Last Frost Date: | Jun. 1 - Jun. 10 |
| Koppen-Geiger Climate Zone: | Dfb - Humid Continental Mild Summer, Wet All Year |
| Ecoregion: | 51n - Platte River Outwash |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 49637 - Grawn, MI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 13 | 13 | 20 | 31 | 41 | 50 | 56 | 55 | 48 | 38 | 29 | 19 | 34 |
| Avg Max Temp (°F) | 27 | 31 | 40 | 53 | 68 | 76 | 80 | 78 | 70 | 58 | 43 | 32 | 55 |
| Avg Precip (In.) | 2.69 | 1.71 | 2.1 | 2.65 | 2.56 | 3.26 | 3.07 | 3.57 | 3.89 | 3.22 | 2.9 | 2.59 | 34.21 |