Bethany, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.7 °F (low) to 59.7 °F (high). Annual precipitation averages 53 Inches. Bethany 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 | 19.0 °F | 35.6 °F | 4.02 in. |
| February | 20.4 °F | 38.1 °F | 3.46 in. |
| March | 27.6 °F | 46.0 °F | 4.8 in. |
| April | 37.9 °F | 58.4 °F | 4.35 in. |
| May | 47.7 °F | 69.3 °F | 4.35 in. |
| June | 57.0 °F | 77.8 °F | 4.5 in. |
| July | 62.4 °F | 82.8 °F | 4.22 in. |
| August | 61.1 °F | 80.9 °F | 4.25 in. |
| September | 54.1 °F | 73.8 °F | 4.71 in. |
| October | 42.5 °F | 62.2 °F | 5.48 in. |
| November | 33.2 °F | 50.9 °F | 4.22 in. |
| December | 24.9 °F | 40.5 °F | 4.61 in. |
| Annual | 40.7 °F | 59.7 °F | 52.97 in. |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 75-100 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 | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |