What and when is “Indian Summer”?
When does Indian summer begin and end, and how did it come to be called Indian summer?
— Henry Schramm, Skokie
Indian summer is a period of at least a few days of sunny, pleasant, dry and unseasonably warm weather, with hazy skies and light winds, that occurs in the Central and Eastern United States from late October through the end of November. The relative humidity is usually quite low. It does not occur every year, but in some years there may be more than one occurrence, and it usually follows a period of colder, frosty weather. The term originated in New England, probably in the late 1700s. The earliest known use of the phrase is in an essay written in the U.S. in 1778 by J. Hector St. John de Crevecoeur. He wrote, “Sometimes the rain is followed by an interval of calm and warm (weather) which is called the Indian summer.”