Glastonbury Center, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41.4 °F (low) to 60.8 °F (high). Annual precipitation averages 49.2 Inches. Glastonbury Center 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 | 19.3 °F | 36.2 °F | 3.68 in. |
| February | 20.6 °F | 38.9 °F | 3.22 in. |
| March | 28.6 °F | 46.9 °F | 4.31 in. |
| April | 38.9 °F | 59.4 °F | 4.11 in. |
| May | 49.0 °F | 70.2 °F | 3.59 in. |
| June | 58.4 °F | 78.7 °F | 4.63 in. |
| July | 63.9 °F | 84.1 °F | 4.14 in. |
| August | 62.3 °F | 82.6 °F | 4.17 in. |
| September | 54.6 °F | 75.3 °F | 4.52 in. |
| October | 43.1 °F | 63.3 °F | 4.81 in. |
| November | 33.3 °F | 51.9 °F | 3.69 in. |
| December | 25.3 °F | 41.7 °F | 4.36 in. |
| Annual | 41.4 °F | 60.8 °F | 49.23 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 | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |