Rockland, Massachusetts has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41 °F (low) to 60.4 °F (high). Annual precipitation averages 50.8 Inches. Rockland is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 19.6 °F | 37.3 °F | 4.28 in. |
| February | 20.8 °F | 39.5 °F | 3.79 in. |
| March | 28.0 °F | 46.5 °F | 5.35 in. |
| April | 37.8 °F | 58.0 °F | 4.63 in. |
| May | 47.5 °F | 68.3 °F | 3.57 in. |
| June | 56.9 °F | 77.4 °F | 3.78 in. |
| July | 63.1 °F | 83.2 °F | 3.39 in. |
| August | 61.5 °F | 81.9 °F | 3.62 in. |
| September | 54.4 °F | 74.7 °F | 3.76 in. |
| October | 43.1 °F | 63.1 °F | 5.08 in. |
| November | 33.8 °F | 52.5 °F | 4.46 in. |
| December | 25.5 °F | 42.8 °F | 5.09 in. |
| Annual | 41 °F | 60.4 °F | 50.8 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |