Forecasters are warning to brace for the coldest week of the year with snow, ice and freezing temperatures expected late on Sunday and Monday morning.
A yellow warning for ice and snow has been issued by the Met Office for the south east, including parts of London, with potential to cause delays on the roads and railways.
That's expected to spread across the rest of England, Wales, Scotland and Northern Ireland on Monday and into Tuesday and Wednesday.
"Wintry showers will continue to fall overnight and into Monday morning, bringing the potential for ice to form where surfaces are left wet. As showers turn increasingly to snow, especially inland, 1-2 cm may accumulate in a few places," the Met Office said for London and the south east.
Temperatures could plunge into the minuses in the capital and as low as -10 in parts of Scotland.
The Met Office's Craig Snell said the first full week of February will likely be "one of our coldest weeeks of this winter so far".