Experts predict that the 25th of December will be warm, with a chance of rain or showers in the south, particularly in the extreme south.

They added that any cold air and snowy conditions would most likely be restricted to the north of the UK, but they warned that their predictions may alter because Sunday is still five days away.

Temperatures jump by 15 degrees as heavy rain predicted
Cold Snap Brings Snow And Freezing Temperatures To London
(Photo : Leon Neal/Getty Images)

As people prepare for their Christmas vacation, the UK's cold snap has given way to high temperatures, with forecasts of severe rain and flooding.

Rain warnings are in effect in southern England and South Wales until 06:00 GMT last Tuesday.

After cold temperatures last week, experts predict highs of up to 15 degrees Celsius in certain areas on Monday.

According to the Met Office, flooding could affect homes and businesses, as well as cause traffic delays.

It also stated that bus and train travel may be hampered when downpours strike cities such as Brighton, Plymouth, and Portsmouth in the south of England, as well as Newport in Wales, on Monday.

Across the country, nine flood warnings and 49 flood alerts have been issued.

As thousands of workers of the Rail, Maritime, and Transport union (RMT) go on strike beginning at 18:00 on Christmas Eve, more individuals may choose to go by car.

According to the RAC, 7.9 million journeys will be undertaken in the two days preceding Christmas Day, with the heaviest congestion forecast between 10:00 and 19:00 on Friday and 12:00 and 13:00 on Saturday.

Following the frigid weather, Peter Jenkins of Water UK asked consumers to verify that their water lines were securely insulated.

Scottish Water reported a 150% increase in broken pipes in recent days due to subzero conditions causing fast thawing, with an additional 100 million liters of water moving through them.

Snow and ice warnings had already been issued for most of the UK up to Sunday, including an amber alert for ice in portions of northern England.

The harsh weather caused significant disruption, with temperatures reaching -17.3 degrees Celsius in Scotland on Tuesday, the lowest high since February 2021.

But the BBC Weather warned on Sunday that the brutally cold, icy weather was transitioning "to something lot warmer, wetter and windier".

"The significant jump in temperatures will be visible on Monday, and while such a sudden fluctuation is rare, it's not unheard of," said presenter Jennifer Bartram.

Also Read: UK Weather: August Bank Holiday Will Be Expected With Heavy Rain While 26C Heatwave Returns Next Week

What's the forecast for Christmas Day

There is a big uncertainty surrounding where the border between these two air masses will finally finish up, especially as we move into the Christmas weekend, Met Office deputy chief meteorologist Dan Harris said of the north-south divide, as per Sky News.

Forecast confidence is unlikely to rise until at least mid-week, and a variety of outcomes remain probable.

Forecasters predict that cooler weather will come in the north by mid-week, while the south will remain balmy.

"Temperatures will vary from mid-single figures in the north to 10C to 12C in the south today," said Sky's weather presenter Jo Wheeler.

This evening, cloud cover will rise from the southwest, followed by showers in the early hours. Some of the rain will become heavy, particularly in Wales and northwestern England.

Wednesday will be "mostly dry" except in the north-west and central portions of Scotland, where showers will persist.

Temperatures will drop another degree or two, with northern areas seeing temperatures ranging from 4 to 6 degrees Celsius and southern areas experiencing temperatures of 9 or 10 degrees Celsius.

Forecasters predict that after Christmas and into the New Year, there may be overnight frosts and early fog, followed by more variable and warmer temperatures.

According to one expert, warmer air from Madeira has suddenly rushed into the UK this week, delivering an "extraordinary" temperature jump following days of frigid temperatures.

Dr. Stephen Burt, a meteorology specialist at the University of Reading, where temperatures shifted from minus 5C last week to 12C on Monday, termed it an "amazing rise of over 20 degrees in a few days".

Related article: Heatwave to Hit the UK in April and Climate Change is to Blame: Met Office Forecast