Needham, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 40.3 °F (low) to 60.2 °F (high). Annual precipitation averages 49.1 Inches. Needham is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.3 °F | 36.4 °F | 3.9 in. |
| February | 19.9 °F | 38.9 °F | 3.43 in. |
| March | 27.3 °F | 46.0 °F | 4.7 in. |
| April | 37.4 °F | 58.1 °F | 4.3 in. |
| May | 47.3 °F | 68.7 °F | 3.66 in. |
| June | 56.6 °F | 77.5 °F | 4.18 in. |
| July | 62.6 °F | 83.3 °F | 3.63 in. |
| August | 61.1 °F | 81.8 °F | 3.84 in. |
| September | 53.7 °F | 74.8 °F | 3.79 in. |
| October | 42.3 °F | 62.8 °F | 4.85 in. |
| November | 33.0 °F | 52.0 °F | 4.06 in. |
| December | 24.6 °F | 41.9 °F | 4.79 in. |
| Annual | 40.3 °F | 60.2 °F | 49.13 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Dfb - Humid Continental Mild Summer, Wet All Year |