midsummer madness

American  

noun

1. a temporary lapse into foolishness, senseless behavior, folly, etc., especially during the summer.

   His plan to become a beachcomber is midsummer madness.

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midsummer madness British  

noun

1. foolish or extravagant behaviour, supposed to occur during the summer

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Etymology

Origin of midsummer madness

First recorded in 1595–1605

Example Sentences

And if the worst comes to the worst, you can always pass it off as midsummer madness.

From The Guardian • Jul. 10, 2015

Referring directly to Lord Cecil's appeal, Chancellor Chamberlain declared, "That is very midsummer madness!"

From Time Magazine Archive

The full force of the midsummer madness struck Western Europe last week.

From Time Magazine Archive

"But this is midsummer madness," said I. "Suppose it is, what matter?"

From Jaffery by Locke, William John

If she had flirted with him, his midsummer madness would have evaporated into thin air; but she kept him at arm's-length, ostensibly took him seriously, and the boy proposed.

From Judith of the Plains by Manning, Marie