It was the same over most of the country as Edinburgh, Glasgow and Birmingham all broke their records for the time of year with temperatures around 16C. The average temperature in February is around 6C.
In Blackpool, ice-cream vans cruised the promenade as children built sandcastles on the beach which was crowded with sunbathers.
At Chester Zoo, an extra admission gate had to be opened to cope with the hordes of people taking advantage of the unseasonal weather.
Chris Vere, a spokesman for the zoo, said: "The lovely weather has made the little animals a lot livelier, the lion cubs are dashing around playing and our baby Indian elephant Sithami has been out with her mum.
"The weather seems to have brought around 1,000 extra people through the gate today."
Around the East Anglian coast, sun-lovers paddled in the sea and lounged on the beach. "There have been people paddling, playing on the beach or just sitting on the sand or the sea wall," said a spokeswoman for the tourist information centre in Lowestoft, Suffolk. "The town has been busy all day with people in short sleeves and one or two in shorts. It's been like a warm spring day.
A spokeswoman for the tourist information centre in King's Lynn, Norfolk, said: "We noticed that all our museums have been very quiet. It's because everyone has headed for the coast at Hunstanton."
The previous record high temperature in Britain during February was at Milford Haven in1972 which notched up 19.4 degrees.
A spokesman from the Meteorological Office said: "The unusually warm weather is due to warm air coming from north Africa bringing unseasonably high temperatures around 10 degrees higher than normal for this time of year."
The unseasonal weather is expected to continue for the next few days although it will be slightly cooler.
"We are not expecting the temperatures to remain quite as high as they are at the moment but it is certainly not going to start freezing," he said.
But the warm weather has caused problems in some Scottish ski resorts where the mild temperatures have caused the snow to melt.
At the Nevis Range ski resort, the highest in the country at 4006ft, there is snow on the higher slopes but visitors were being advised to bring their walking boots as well as ski gear.
Cally Fleming, marketing manager at the range, said: "We are beginning to worry about [the lack of snow] but we often get a large fall in March and April so we are hopeful that it will not be a totally bad season."