Brookline, Massachusetts has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.3 °C (low) to 15.7 °C (high). Annual precipitation averages 1263.9 Millimeters. Brookline is located in USDA Plant Hardiness Zone 6b. 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 | -6.9 °C | 2.7 °C | 101.6 mm |
| February | -6.1 °C | 4.1 °C | 92.46 mm |
| March | -2.1 °C | 7.8 °C | 123.7 mm |
| April | 3.6 °C | 14.3 °C | 109.47 mm |
| May | 9.1 °C | 20.1 °C | 93.47 mm |
| June | 14.3 °C | 25.2 °C | 106.17 mm |
| July | 17.6 °C | 28.4 °C | 93.98 mm |
| August | 16.8 °C | 27.5 °C | 95.76 mm |
| September | 12.7 °C | 23.6 °C | 95.76 mm |
| October | 6.4 °C | 17.2 °C | 122.94 mm |
| November | 1.2 °C | 11.3 °C | 102.87 mm |
| December | -3.4 °C | 5.8 °C | 125.73 mm |
| Annual | 5.3 °C | 15.7 °C | 1263.91 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |