Stafford Springs, Connecticut has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.3 °C (low) to 14.8 °C (high). Annual precipitation averages 1236.7 Millimeters. Stafford Springs is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.8 °C | 1.4 °C | 83.82 mm |
| February | -8.4 °C | 2.8 °C | 75.95 mm |
| March | -4 °C | 7.1 °C | 102.87 mm |
| April | 1.7 °C | 14.1 °C | 103.12 mm |
| May | 7.3 °C | 20.1 °C | 90.93 mm |
| June | 12.6 °C | 24.7 °C | 115.32 mm |
| July | 15.8 °C | 27.5 °C | 101.09 mm |
| August | 14.7 °C | 26.6 °C | 113.54 mm |
| September | 10.7 °C | 22.8 °C | 116.84 mm |
| October | 4.3 °C | 16.2 °C | 128.52 mm |
| November | -0.9 °C | 10 °C | 92.96 mm |
| December | -5.3 °C | 4.5 °C | 111.76 mm |
| Annual | 3.3 °C | 14.8 °C | 1236.72 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |