Britain is set to warm up over the weekend before sizzling in temperatures more akin to mid-summer next week, say forecasters.
BBC meteorologist Tomasz Schafernaker said: "The temperatures, on Sunday, given a bit of sunshine in the south of the country could exceed 20 degrees and the current indications are that as we head into next week it's going to feel like June or July."
Met Office weather maps, meanwhile, show temperatures hitting 23C in London by Tuesday, with meteorologist Nicola Maxey predicting a return of highs "above average for this time of year".
The national weather service's long range report says: "Temperatures look to take an upward trend over the next two weeks with most areas becoming warm, especially in the south and east.
"Most places should remain largely dry with plenty of brightness or sunshine as well as light winds."
It's a far cry from yesterday with overnight temperatures into Thursday plummeting well below zero.
Katesbridge in Northern Ireland saw its lowest temperature ever recorded in May on Thursday morning at minus 6.1C, said The Met Office.
Previously the area had recorded a record low for May of minus 5.2C in 1995.
The freezing temperatures were almost as cold as Northern Ireland's record low of minus 6.5C, recorded in Moydamlaght, Londonderry, in 1982.
While temperatures in Shap, Cumbria, dropped to minus 4.6C and in North Yorkshire minus 4C was recorded.
But they did not get close to the lowest temperature ever recorded in May for the UK, which was minus 9.4C, in Lynford, Norfolk, in 1941.
Met Office spokeswoman Nicola Maxey said: "We are slowly seeing day-on-day warming and we are seeing temperatures pick up, certainly by Sunday in London when we'll see temperatures of 20 or 21C."
Temperatures are expected to reach up to 18C in the capital today, with highs above 14C in other parts of the country.
But while those in the south and east of the country will be able to make the most of unlimited exercise, north-west Scotland, Northern Ireland and north-west England could face a wet weekend, with a weather front bringing heavy rain on Saturday, Sunday and Monday.
Ms Maxey said: "By the time we get to the middle of next week, temperatures will be in the 20s and we could even start seeing them up towards the mid-20s.
"We will be seeing the return of warmer weather and temperatures above average for this time of year."
She said the cold snap had been caused by a high-pressure system bringing cold air from the north, but next week would see air from the south warming things up.
UK 5 day weather forecast
Today:
Many areas dry with some sunshine and temperatures slightly higher for most. Cloudier across the north of Scotland with some rain or showers. These most frequent in the far north and accompanied by brisk winds.
Tonight:
Variable cloud and clear spells, best in the south. A few showers likely in the north with more persistent rain in northern Scotland. Colder with wintry showers for Shetland.
Saturday:
Many areas dry with sunny spells and feeling rather warm. Cloudy across the north and west of Scotland and later Northern Ireland with occasional rain.
Outlook for Sunday to Tuesday:
Southern areas dry throughout and turning warmer. Showery in the northwest on Saturday. Rain across northern and some central areas on Sunday becoming largely confined to the northwest on Monday
