Boston, Massachusetts has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.1 °F (low) to 59.8 °F (high). Annual precipitation averages 49.6 Inches. Boston is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 21.3 °F | 37.1 °F | 4.05 in. |
| February | 22.8 °F | 39.3 °F | 3.69 in. |
| March | 29.6 °F | 45.5 °F | 4.92 in. |
| April | 39.8 °F | 57.0 °F | 4.35 in. |
| May | 49.4 °F | 67.3 °F | 3.57 in. |
| June | 59.1 °F | 76.7 °F | 4.12 in. |
| July | 65.1 °F | 82.6 °F | 3.64 in. |
| August | 63.9 °F | 80.9 °F | 3.67 in. |
| September | 56.8 °F | 73.7 °F | 3.72 in. |
| October | 45.7 °F | 62.6 °F | 4.87 in. |
| November | 36.2 °F | 52.0 °F | 4.08 in. |
| December | 27.6 °F | 42.5 °F | 4.96 in. |
| Annual | 43.1 °F | 59.8 °F | 49.64 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |