Commuters faced knock-on delays during rush-hour and into the evening after a day of snowfall as Britain’s cold spell continues its grip.
Met Office weather warnings for snow for much of the country are in place until Saturday, with snow showers and longer periods of snow expected throughout Tuesday evening.
Southern railway said disruption to services may continue until Thursday, with knock-on delays throughout Tuesday as trains ran at reduced speeds.
It and Great Northern have advised passengers to complete their journeys “as early as possible” on Tuesday, with more snow forecast into the night.
Greater Anglia said it was hoping to resume a full service on Wednesday but that there may be delays and disruption to services over the course of the day.
The Met Office is also warning of the potential for some rural communities to become cut off, and that power cuts and disruption to mobile phone services may occur.
Met Office forecaster Mark Wilson said the UK was facing “an exceptionally cold” night, with the potential for the mercury to dip as low as -10C in parts of Scotland.
There is further heavy snow forecast overnight for the North East and eastern parts of Scotland and isolated showers elsewhere, he said.
Motorists have been warned to take extra care on the roads due to the snowy conditions, after four people died in car crashes amid the heavy snow.
Three were killed in a crash in Lincolnshire and another man died after a collision in Cambridgeshire on Tuesday morning.
And hundreds of schools have been closed across the UK, including more than 200 in Wales, 131 in Kent and 62 in East Sussex.
Conditions are not likely to improve for several days, with forecasters warning that snow will continue well into the week.
Forecaster Frank Saunders said parts of the country could see their “coldest spell of weather since at least 2013, and possibly since 1991”.
It is expected that the mercury could plummet to minus 15C by midweek where there is snow on the ground, rivalling temperatures forecast for parts of northern Norway and Iceland.
The storm, named by the Portuguese Met Service, will move north through Europe and is due to hit the UK on Thursday and Friday, and will be “significantly disruptive”, bringing the risk of power cuts and transport delays.