The weather warning for snow which covers York and North Yorkshire has been upgraded.
The Met Office has now issued an amber warning for snow for most of the north of England.
It runs from 9pm tomorrow (Saturday) till 11.59pm on Sunday.
Forecasters say: “Snow will reach the south of the warning area later Saturday, then spread north across the rest of the area through Sunday morning.
“Snow will be persistent and heavy at times, and will likely drift in brisk easterly winds, especially over higher ground.
“Much of the warning area can expect 3-7 cm of snow. Areas above about 150 m will likely see 15-30 cm, with 40 cm for ground above 300 m, before snow begins to ease and clear by the end of Sunday.
“For some lower-lying areas, such as the Vale of York, snow may mix with rain at times making estimations of snow depths here more difficult. Regardless, travel will likely be difficult, with power line icing an additional impact.”
Met Office chief forecaster Jason Kelly said some “significant accumulations” of snow are possible in parts of Wales, the Midlands and northern England, and the additional factor of strengthening winds could lead to drifting of lying snow.
National Highways advised those planning to travel over the weekend to check their vehicles, keep their distance on the roads and pack a “snow kit” of blankets, food, water and a shovel.
UK Health Security Agency (UKHSA) cold weather health alerts for all of England remain in place ahead of a week of low temperatures.
Amber alerts were issued on Thursday and will run until January 8, meaning a rise in deaths is likely, the agency said.