Its forecasters issued a yellow weather warning for heavy rain and snow across the capital and swathes of the South East until 10am on Friday.
It suggested slush and water could affect driving conditions, while bus and train services could also be affected.
The alert added: ” In a few places 1-2cm of snow could accumulate, mainly on grassy surfaces over the North Downs and Chilterns.”
Twitter users have already complained of “road chaos” as cars crawl along icy, gritted routes.
Essex police shared a photo of one of their officers patrolling the roads, with the caption: “The weather outside is frightful!"
However, the coldest weather is expected in north west Scotland overnight where temperatures could plunge as low as -10C.
— Essex Police in Colchester #StayAlert (@EPColchester) December 4, 2020
Thursday was the UK’s coldest night of autumn/winter so far, with -9.6C recorded at Altnaharra, Sutherland, in the Highlands.
But the chilliest night of 2020 is still February 13, when the mercury hit -10.2C at Braemar in Aberdeenshire.
Met Office meteorologist Alex Burkill said the “most significant snow” was likely to fall in England, in Cumbria and the Pennines – where some areas could see up to 10cm.
“That’s a significant amount of snow especially this early in December,” he said.
“The snowiest months are usually a bit later into winter, January and February and also it’s very early in December at the moment.”
Mr Burkill added that the conditions could “quite easily make it the coldest night of the year so far”.
A number of yellow warnings for ice and snow remain in place across large areas of Scotland and Northern Ireland and stretch down into North Yorkshire, with further suggestions of possible travel disruption.
Snow in parts of Scotland left motorists tackling difficult driving conditions while Edinburgh residents reported “thundersnow” in the early hours.
Met Office meteorologist Aidan McGivern described early Friday as being that “awkward mixture of cold rain, sleet and falling snow” for many areas of Britain.
The forecaster said the cold spell is expected to last through the day, but the weekend should see brighter weather and even some sunshine.
It added that temperatures going into next week would be lower than the average annual temperature, which is usually about 7C to 9C.