Wellfleet, Massachusetts has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 44.7 °F (low) to 58.2 °F (high). Annual precipitation averages 44.8 Inches. Wellfleet is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 25.9 °F | 38.6 °F | 3.96 in. |
| February | 26.5 °F | 39.0 °F | 3.16 in. |
| March | 31.3 °F | 44.0 °F | 4.2 in. |
| April | 39.7 °F | 53.0 °F | 4.14 in. |
| May | 48.4 °F | 62.8 °F | 2.99 in. |
| June | 57.6 °F | 72.5 °F | 3.29 in. |
| July | 64.6 °F | 79.2 °F | 2.45 in. |
| August | 64.1 °F | 78.0 °F | 3.45 in. |
| September | 58.5 °F | 72.0 °F | 4.03 in. |
| October | 48.7 °F | 61.7 °F | 4.66 in. |
| November | 39.5 °F | 52.3 °F | 4.12 in. |
| December | 32.0 °F | 44.7 °F | 4.38 in. |
| Annual | 44.7 °F | 58.2 °F | 44.83 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |