Autumn is a season known for colorful leaves and falling temperatures. Every once in a while, however, summer warmth makes a resurgence. When this happens, it is often dubbed “Indian Summer”.
This weather phenomenon, according to the NWS glossary, is defined as “an unseasonably warm period near the middle of autumn, usually following a substantial period of cool weather.” In the northeastern US, it is generally associated with an area of high pressure to the south that ushers warm air northward.
In popular use since the 18th century, the exact origins of the term are a bit foggy. One of the more reasonable explanations behind this unique phrase suggests a connection to when Native Americans began their hunting season, but no one knows for sure.
In other parts of the world, this summer-like weather goes by a variety of different names. In Europe, a number of countries associate the unusual warmth with the nearest saint’s day. It is known as “St. Luke’s Little Summer” if it develops in October or a “St. Martin’s Summer” if it occurs in November. In temperate parts of South America, it is simply known as “Veranico” (little summer).
The timing and intensity of these autumn warm spells vary from year to year. Nevertheless, when they do occur, they usually only last a few days. So, as we inevitably move toward winter, enjoy them while you can.
Fall foliage. Credit: Melissa Fleming