Yellow snow warnings have been issued by the Met Office as a "mini Beast from the East" looks poised to impact Britain.
Temperatures will tumble this weekend as a bitter blast brings the potential for up to 5cm in some parts and 20cm on higher ground.
Meteorologist Martin Bowles said snow will first appear on Friday afternoon, impacting north-eastern Scotland and north-eastern England, before the weather front rolls across the rest of Britain.
"On Saturday that snow band in the east starts to move further south - including affecting south-east England and London - it will weaken as it does so," he said.
"On Sunday we get that snow spreading more widely particularly further west and into the south of England - Devon, Kent, the Midlands and parts of Wales."
Mr Bowles said that in certain areas where the snow is gathered, up to 5cm could be seen, which he said is "enough to cause a fair amount of disruption to transport".
The Met Office warnings for snow and ice begin at 3pm on Friday for central Scotland and the north east, and run into all of Saturday where more of England is included.
The warning for all of Sunday, when "significant snowfall" is expected, shows vast swathes of the south, central and east of England covered by the yellow advisory.
Asked about the possibility of some of the snow warnings being upgraded, Mr Bowles said "amber is certainly a possibility" on Sunday, but that a red warning is "extremely unlikely".
He added: "We don't expect it to be Beast from the East Mark Two, you could call it a mini Beast from the East I suppose as it is a less severe version of it.
"We don't expect anything like the same impact as a result of it, although there will be some snow about."
Mr Bowles said from Saturday and Sunday "very cold temperatures for this time of year will affect the whole of the UK", with ice a potential issue for many.
"By Sunday we expect the maximum temperatures to be only 1C and some parts will stay below freezing all day... it is probably the coldest day of the lot," he added.
He said the bitterly cold blast will be "fairly short lived", with low temperatures still around on Monday before the mercury rises "fairly rapidly" from Tuesday.