| 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 |
| 1990 Hardiness Zone: | Zone 1b: -15F to -10F |
| 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: | 56d - Michigan Lake Plain |
| Heat Zone Days: | Rare Over 86°F |
Annual Climate Data for ZIP Code 49449 - Pentwater, MI | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Annual |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg Min Temp (°F) | 16 | 17 | 24 | 34 | 43 | 52 | 58 | 57 | 50 | 40 | 31 | 21 | 37 |
| Avg Max Temp (°F) | 29 | 33 | 42 | 55 | 68 | 76 | 80 | 78 | 70 | 59 | 45 | 34 | 56 |
| Avg Precip (In.) | 2.04 | 1.4 | 2.16 | 2.8 | 2.87 | 3.19 | 2.68 | 4.08 | 3.72 | 3.49 | 3.27 | 2.44 | 34.14 |