Despite the name, an Indian Summer is an autumnal event. It is defined as a period of unseasonably warm, dry, calm, hazy weather that occurs in October and November after a hard/killing freeze or snowfall.

There may be several Indian Summers within a fall season, or none at all. It's abnormally warm and dry conditions last anywhere from several days to well over a week.

This explains the term's reference to "summer," but what about the reference to Indians?


 Does this seasonal weather phenomena have anything at all to do with Native Americans?

Why the Controversial Name?

The origins of the phrase "Indian Summer" are as hazy as the weather conditions it's known to bring. However, one thing is clear -- the term was likely coined along the American east coast by early European settlers who would have been very observant of the weather conditions as well as the movements of the Native Americans, or American Indians, who inhabited the land.  

One explanation of the term is that it was the time of year when the early native Indians hunted. (The mild weather would have encouraged animals back out of their dens, and the haziness of the air would have given hunters the advantage of sneaking upon their prey.) Another related idea was that the Indians made use of this weather to attack not animals, but the white settlers before the winter set in.

Yet another explanation Some say it comes from the early Algonquian Native Americans, who believed the warm spell was caused by a warm wind sent from the court of their southwestern god, Cautantowwit.

Yet another probable explanation is it was a welcome last chance to get one's goods to port and loaded onto ships bound for the Indian Ocean (and later the west Indies-a historic trading port).

Out of all of these possible theories, no single one has been accepted as the term's origin.

High Pressure 

A typical weather pattern that leads to Indian Summer is a large area of high pressure positioned just off of the East Coast. Ironically, such high pressure systems usually enter the U.S. as a polar air mass out of Canada. After bringing frost and freeze conditions The clockwise rotation of winds around the high pressure center pull warmer temperatures from the Gulf northward on the wings of southerly breezes. 

Indian Summers in the U.S.

Given that a hard freeze is prerequisite of an Indian Summer, . ranging from the Mid-Atlantic states north into New England and westward across the Ohio Valley, Great Lakes, Midwest, and the Great Plains. (Take a peek at these maps to help envision where these regions are...)