Rockland, Michigan has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1 °C (low) to 10.6 °C (high). Annual precipitation averages 859.5 Millimeters. Rockland is located in USDA Plant Hardiness Zone 4b. 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 | -14.3 °C | -5.4 °C | 66.55 mm |
| February | -14.8 °C | -3.4 °C | 43.18 mm |
| March | -10.3 °C | 2.6 °C | 43.94 mm |
| April | -2.9 °C | 9.6 °C | 64.26 mm |
| May | 3.9 °C | 17.7 °C | 82.3 mm |
| June | 9.3 °C | 23.1 °C | 81.79 mm |
| July | 12.1 °C | 25.3 °C | 87.63 mm |
| August | 11.3 °C | 24.4 °C | 76.71 mm |
| September | 7.4 °C | 19.9 °C | 84.58 mm |
| October | 1.4 °C | 12.1 °C | 90.68 mm |
| November | -4.5 °C | 3.7 °C | 69.85 mm |
| December | -10.5 °C | -2.7 °C | 68.07 mm |
| Annual | -1 °C | 10.6 °C | 859.54 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 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |