What is an Indian Summer?

Shipton Gorge hill, Dorset Credit: Andrew Miller

With the possibility of high temperatures during the autumn months there are often mutterings of whether or not we're heading for an Indian Summer, but is that really a thing, and what does it mean?

Summer weather at the Lizard lighthouse Credit: Nichola Peters

We often have a spell of warm weather during the autumn months and the last few Septembers have come up trumps with a few fine and warm days. Back in 2016 we had temperatures around 30 °C for instance. However, a true Indian Summer tends to occur a bit later in the season during October or November.

The history of the name is uncertain but it's thought to originate from the eastern United States of America back in the 18th Century, where spells of warm weather in autumn allowed Native American people to carry on hunting.

It was the early 19th Century before 'Indian Summer' was used in the UK, but there is no statistical evidence to suggest there's a certain time each year that we may see warm autumn weather develop. What's commonly agreed however, is that there must be a widespread frost before the heat returns.

Thick frost in Abbotsham, north Devon Credit: Simon James

So how warm does it get? Well, it's not that rare to see temperatures in the 30s during September; the record is 35.6 °C at Bawtry in South Yorkshire. October's highest temperature is 29.9 °C at Gravesend, Kent, and we've seen November highs of 22.4 °C at Trawsgoed in Ceredigion! Where did I put those flip flops...