It's still hot in many parts of the UK, but some tree leaves are turning yellow and blackberries are so ripe in hedges that they're tasting alcoholic.
Councils in London have issued "do not sit under trees" warnings because of the dangers of dying branches suddenly falling.
What's going on? Is it still summer, or has autumn started already? And does it matter anyway?
There is no formal definition of "early autumn" but experts say signs of the season, like leaves falling or apples being ready to pick, are actually nature becoming stressed by the long hot and dry summer.
And a potentially historic one at that - the Met Office says this summer is on track to be one of the warmest since records began in 1884.
