Britain will enjoy some unseasonal balmy weather this week, thanks to an extended blast of tropical air.

Parts of the England and Wales are expected to reach at least 20C over the coming days - five degrees above average - as warm southern winds stave off an autumnal chill.

Virtually all parts of the UK will bask in the Indian summer conditions, with the mercury expected to reach 17 degrees as far north as Glasgow.

The heatwave will make the week one of the warmest for late October on record. The highest temperature for this time of the year stopped just short of 23 degrees in 1996.

Brendan Jones, a forecaster at MeteoGroup, the weather division of the Press Association, said: "It's going to be very warm.

"Somewhere across England and Wales, any time between today and Friday, we will definitely get to 20 degrees - it could be just about anywhere."

The balmy conditions are being enjoyed by families across the country, with many schools closed for the half-term break.

It is being produced by a low pressure out in the Atlantic and a high pressure over Scandinavia, which are sending warm winds up from southern France and central Africa.

Mr Jones said it would be warmest in the South East between now and Friday, with more chance of showers in the north of the UK. "There will definitely be no frost," he added.

Rain is expected to return for most people by the weekend.