Riverton, Connecticut has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 38.3 °F (low) to 59.5 °F (high). Annual precipitation averages 51.6 Inches. Riverton 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 | 15.9 °F | 34.2 °F | 3.67 in. |
| February | 17.2 °F | 37.3 °F | 3.22 in. |
| March | 24.9 °F | 45.4 °F | 4.19 in. |
| April | 35.5 °F | 58.7 °F | 3.9 in. |
| May | 46.2 °F | 69.9 °F | 4.15 in. |
| June | 55.7 °F | 78.3 °F | 4.83 in. |
| July | 60.7 °F | 83.2 °F | 4.58 in. |
| August | 58.9 °F | 81.3 °F | 4.45 in. |
| September | 51.4 °F | 74.2 °F | 4.93 in. |
| October | 40.2 °F | 61.7 °F | 5.31 in. |
| November | 30.8 °F | 50.2 °F | 3.92 in. |
| December | 22.5 °F | 39.3 °F | 4.48 in. |
| Annual | 38.3 °F | 59.5 °F | 51.63 in. |
| 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 : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |