Grayling, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.2 °C (low) to 12.2 °C (high). Annual precipitation averages 873.5 Millimeters. Grayling is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -12.2 °C | -3.3 °C | 51.82 mm |
| February | -12.8 °C | -1.7 °C | 38.86 mm |
| March | -8.7 °C | 4.1 °C | 45.72 mm |
| April | -1.7 °C | 11.2 °C | 85.6 mm |
| May | 5 °C | 19.1 °C | 86.36 mm |
| June | 10.2 °C | 24.4 °C | 96.77 mm |
| July | 12.5 °C | 26.4 °C | 80.77 mm |
| August | 11.6 °C | 25.6 °C | 83.31 mm |
| September | 7.3 °C | 21.4 °C | 82.04 mm |
| October | 1.9 °C | 13.4 °C | 101.85 mm |
| November | -3.1 °C | 5.8 °C | 69.34 mm |
| December | -7.8 °C | -0.3 °C | 51.05 mm |
| Annual | 0.2 °C | 12.2 °C | 873.49 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |