Sherman, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.5 °F (low) to 59.8 °F (high). Annual precipitation averages 49.6 Inches. Sherman 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. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 17.1 °F | 35.2 °F | 3.44 in. |
| February | 19.0 °F | 38.2 °F | 2.82 in. |
| March | 26.3 °F | 46.3 °F | 3.81 in. |
| April | 37.1 °F | 59.2 °F | 3.88 in. |
| May | 47.3 °F | 69.8 °F | 3.79 in. |
| June | 56.4 °F | 77.9 °F | 4.59 in. |
| July | 61.8 °F | 83.0 °F | 4.69 in. |
| August | 60.3 °F | 81.2 °F | 4.9 in. |
| September | 52.9 °F | 73.9 °F | 4.67 in. |
| October | 41.2 °F | 62.2 °F | 4.95 in. |
| November | 31.6 °F | 51.0 °F | 3.82 in. |
| December | 23.5 °F | 40.0 °F | 4.2 in. |
| Annual | 39.5 °F | 59.8 °F | 49.56 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |