Saint Martin's summer

American  

noun

1. mild, warm weather similar to Indian summer, occurring in November.

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Saint Martin's summer British  

noun

1. a period of unusually warm weather in the late autumn, esp early November

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Etymology

Origin of Saint Martin's summer

First recorded in 1585–95; from the occurence of such weather around the feast of St. Martin, celebrated on November 11

Example Sentences

Saint Martin's Summer is the traditional British phrase for warm weather well into autumn.

From BBC

They were then in Saint Martin's summer, the time of sowing, and the labourer divided the broken-up earth into three parts.

From Project Gutenberg

And if he did not look to the future that sweet December night of Saint Martin's summer by the placid Tennessee River, perhaps it was as well,—oh, poor Captain Demer�!

From Project Gutenberg

The Saint Martin’s summer lasted to the beginning of December, and then it came to an end, and with it the idyll of Aristide and Anne Honeywood.

From Project Gutenberg

A few rough rainy days stripped the trees of their foliage; and although the sun shone out again and made lovely weather, Saint Martin's summer, halcyon days, it was plain to all the senses that the autumn was drawing to a close.

From Project Gutenberg