It was a foggy start on Monday morning - with commuters in the capital noting the misty October weather.
But never fear - it's supposed to get hot later in the day with temperatures climbing to a maximum of 20C in London.
The fog has even caused some cancellations of flights travelling to London and landing at Heathrow, London City Airport and Gatwick.
After that, the forecast is looking wintry with the weather in the UK set to get distinctly chilly.
Mists and mellow fruitfulness: The sunrise was looking distinctly autumnal
To mark the change in the temperature we asked readers to send in their weather pictures - see below to see if yours made the slideshow.
HuffPost Readers' Autumn Pics
Alexi Boothman, a forecaster with Meteogroup said: "Clearly, it is a gradual decrease in temperatures from the beginning of the week and it is quite a marked fall in the space of a week with the air mass being turned around."
To send in your Autumn pics, email ukpicturedesk@huffingtonpost.com