Lynnfield, Massachusetts has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.8 °C (low) to 15.3 °C (high). Annual precipitation averages 1258.3 Millimeters. Lynnfield 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 | -7.6 °C | 2.2 °C | 97.03 mm |
| February | -6.6 °C | 3.6 °C | 91.44 mm |
| March | -2.6 °C | 7.4 °C | 119.63 mm |
| April | 3.1 °C | 14.2 °C | 110.24 mm |
| May | 8.6 °C | 19.7 °C | 93.98 mm |
| June | 13.9 °C | 24.9 °C | 108.46 mm |
| July | 17.2 °C | 28.1 °C | 97.28 mm |
| August | 16.4 °C | 27.3 °C | 93.22 mm |
| September | 12.3 °C | 23.3 °C | 99.82 mm |
| October | 5.9 °C | 16.8 °C | 122.94 mm |
| November | 0.7 °C | 10.9 °C | 102.36 mm |
| December | -4 °C | 5.3 °C | 121.92 mm |
| Annual | 4.8 °C | 15.3 °C | 1258.32 mm |
| 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 : -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 |