Under the Köppen climate classification, Bridgeport has a warm temperate climate (Cfa), with long, hot summers, and cool to cold winters, with precipitation spread fairly evenly throughout the year. Bridgeport, like the rest of coastal Connecticut, lies in the broad transition zone between the colder continental climates of the northern United States and southern Canada to the north, and the warmer temperate and subtropical climates of the middle and south Atlantic states to the south.
The warm/hot season in Bridgeport is from mid-April through early November. Late day thundershowers are common in the hottest months (June, July, August, September), despite the mostly sunny skies. The cool/cold season is from late November though mid March. Winter weather is far more variable than summer weather along the Connecticut coast, ranging from sunny days with higher temperatures to cold and blustery conditions with occasional snow. Like much of the Connecticut coast and nearby Long Island, NY, most of the winter precipitation is rain or a mix and rain and wet snow in Bridgeport. Bridgeport averages about 33 inches (85 cm) of snow annually, compared to inland areas like Hartford and Albany which average 45–60 inches (110–150 cm) of snow annually.
Although infrequent, tropical cyclones (hurricanes/tropical storms) have struck Connecticut and the Bridgeport metropolitan area. Hurricane landfalls have occurred along the Connecticut coast in 1903, 1938, 1944, 1954 (Carol), 1960 (Donna), Hurricane Gloria in 1985, and Hurricane Sandy in 2012.
Bridgeport lies in USDA garden zone 7a, averaging about 92 days annually with freeze. Coastal Connecticut is the broad transition zone where so-called “subtropical indicator” plants and other broadleaf evergreens can successfully be cultivated. As such, Southern Magnolias, Needle Palms, Windmill palm, Loblolly Pines, and Crape Myrtles are grown in private and public gardens. Like much of coastal Connecticut, Long Island, NY, and coastal New Jersey, the growing season is rather long in Bridgeport—averaging 210 days from April 8 to November 5 according to the National Weather Service in Bridgeport.
The average monthly temperature ranges from 31.4 °F (−0.3 °C) in January to 75.7 °F (24.3 °C) in July. The record low is −7 °F (−22 °C), set on January 22, 1984, while the record high is 103 °F (39 °C), set on July 22 in 1957 and 2011.
Precipitation averages 44.9 inches (1,140 mm) annually, and is somewhat evenly distributed throughout the year, with March and April the wettest months. Annual snowfall averages 33.6 inches (85 cm), falling almost entirely from December to March. As is typical of coastal Connecticut, snow cover does not usually last long, with an average of 33 days per winter with snow cover of at least 1 inch (2.5 cm).