Bloomfield, Connecticut has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5 °C (low) to 15.9 °C (high). Annual precipitation averages 1322.1 Millimeters. Bloomfield 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.4 °C | 1.9 °C | 94.23 mm |
| February | -6.7 °C | 3.5 °C | 83.06 mm |
| March | -2.3 °C | 8.1 °C | 110.24 mm |
| April | 3.6 °C | 15.3 °C | 106.17 mm |
| May | 9.3 °C | 21.4 °C | 98.81 mm |
| June | 14.5 °C | 26.2 °C | 120.4 mm |
| July | 17.4 °C | 29.2 °C | 110.49 mm |
| August | 16.6 °C | 28.2 °C | 113.28 mm |
| September | 12.4 °C | 24.1 °C | 122.43 mm |
| October | 6 °C | 17.3 °C | 140.46 mm |
| November | 0.6 °C | 10.8 °C | 103.89 mm |
| December | -3.9 °C | 4.9 °C | 118.62 mm |
| Annual | 5 °C | 15.9 °C | 1322.08 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |