With bright sunny mornings and balmy afternoons, this year's autumnal weather has been more typical of Greece or Spain.
The average daily temperature has climbed to 13.3C, two degrees warmer than usual, and is on course to be the hottest October on record.
According to the Meteorological Office, daytime temperatures should be about 13C at this time of year - although recently that has climbed to 21C.
"There are still 20 days to go until the end of October, which is a transitional month in terms of weather, but the record may be broken this year," a Met Office spokesman said.
He added: "The monthly average of 13.3C has already equalled the hottest October ever recorded in 2001."
According to the forecaster, the warm weather has been caused by high pressure on the Continent, which puts the UK in line with southerly winds bringing up warm air from the Mediterranean.
This explains why earlier this week in London the temperature rose to 21C, compared with the average maximum of 18C.
And there will be no imminent need to dust down the winter wardrobe, according to the Met Office, as the weather is set to be fair for the next five days. "It's looking pretty settled," the spokesman said.
If October breaks the records, it will be the third month this year to do so. July was the hottest on record with temperatures of 36.5C and September temperatures of 15.4C broke the 1949 record of 14.7C.Reuse content