Green Bay has a humid continental climate (Köppen climate classification "Dfb"), with some moderation due to the city's proximity to Lake Michigan. Like other cities with this type of climate, there are four distinct seasons, often with severe or extreme variation between them in terms of temperature and precipitation. Green Bay experiences warm, humid, frequently hot summers and long, cold and snowy winters. The variance in temperature and precipitation between months is severe and often extreme. Tornadoes are rare in the Green Bay area, with the strongest being an F3 tornado that hit the community of Pittsfield on June 26, 1969.