Dunkelflaute 2025 Calendar. Choose from options that include us federal holidays, customizable blank calendars, and convenient. Select a date to see detailed holiday information for countries worldwide.

1902, 1913, 1919, 1930, 1941, 1947, 1958, 1969, 1975, 1986, 1997, 2003, and 2014. Dark doldrum) describes the simultaneous occurrence of darkness and a lull in wind activity.