I remember that back in the 1990s Chicago experienced its longest sunless stretch. How long did it last?
Chicago’s climate records date back to 1871 and have included sunshine data since the fall of 1893, tabulating the minutes of sunshine recorded daily. During that period the longest stretch of totally cloudy days (zero minutes of sunshine) is 12, extending from December 29, 1991-January 9, 1992. Skies were overcast, both day and night, allowing for little daytime warming and nighttime cooling. During that dismal 12-day period Chicago temperatures varied by just 14 degrees, ranging from a high of 44 to a low of 30. The November-February period accounts for the vast majority of the city’s totals cloudy days with 65 percent of them occurring during those four months.