Groton has four distinct seasons, marked by hot summers and cold winters. Highs top out in the summer months, particularly July and August when the average highs are in the lower 80s. During these months, lows are in the lower-60s. The coldest months of the year are December and January. Highs during the winter are in the upper 30s to lower 40s, and lows typically dip below freezing as much as ten degrees for average lows in the lower 20s. The highest temperature recorded in Groton was 101 degrees F in 1991. The lowest temperature recorded was -14 Fahrenheit degrees in 1961.

    Groton's precipitation is dispersed evenly throughout the year, without a distinct dry or wet season. Each month receives about four inches of rain. November has slightly more rain on average and is the wettest month historically. Since lows are below freezing from November through March, this means that Groton receives a significant amount of snow during this time. 

    For a detailed local forecast for Groton, check out the Weather Channel's Groton weather page, here