South London must endure one more day of bitterly cold weather before temperatures soar on Monday in stark contrast to the chilly temperatures recorded over the last week.
Within 24 hours, temperatures are expected to jump and the cold snap will be replaced with warmer weather due to milder air coming in from the Atlantic.
In South London, temperatures on Saturday were expected to hit a high of 5C, while on Monday they could hit 14C.
A yellow weather warning is currently in place for London between 3am and 2pm (December 18).
The Met Office warns of some risk of injuries from slips and falls on icy surfaces, icy patches on some untreated roads, pavements and cycle paths and potential travel disruption.
A level three cold weather alert was earlier issued by the UK Health Security Agency (UKHSA) for all of England until midnight on Sunday, which it warns could “increase the health risks to vulnerable patients and disrupt the delivery of services”.
Met Office forecaster Marco Petagna said both daytime and night-time temperatures are expected to increase over the next couple of days.
He told the PA news agency: “At the moment daytime temperatures are low single figures, and in places are staying below freezing under snow cover, so some areas are just a little bit below zero.
“But daytime temperatures by Monday, we’re looking at across the UK highs of 11C to 14C, so around about 15 degrees certainly higher than they’ve been.”
Mr Petagna said people can expect a leap of “15 degrees or more” as some snow-covered spots could see an increase of more than 15 degrees.
Mr Petagna said cold wind has been coming down from the north in the last week or 10 days, but this week winds are going to start coming in from the west or south west.
“So it’s bringing milder air off the Atlantic, rather than coming down from the Arctic,” he said.
Mr Petagna said it is not unheard of to get temperatures in the low teens at this time of year, but said the contrast of going from very cold to very mild in a day or two is quite unusual.
Peter Jenkins, director of campaigns at Water UK, advised that the rise in temperature could cause burst pipes.
He said: “The recent freezing weather has been very disruptive to many people.
“The last thing we want is for people to experience further disruption as temperatures rise this weekend, putting many homes at risk of burst pipes due to freeze-thaw.
“That’s why we’re urging everyone to check their water pipes are well insulated now and to follow our simple tips to protect homes against weather conditions.”
Today weather forecast reads: “Any early freezing fog patches soon clear as wind and cloud increases. Brief outbreaks of sleet and hill snow will spread northeast from late morning, with bands of heavy rain following shortly after. Becoming much milder from the southwest. Maximum temperature 10 °C.”
Tonight you can expect: “Further bands of heavy rain progressing northeastward through the evening and overnight. Remaining cloudy with blustery winds. Less cold than recent nights. Minimum temperature 6 °C.”
Mondays forecast reads: “A wet and windy day, with outbreaks of rain arriving from the southwest. Cloudy throughout, with a chance of some heavy downpours later in the day. Feeling rather mild. Maximum temperature 13 °C.”