Brits are told to brace for an Arctic blast as yellow warnings are issued around the country.
The Met Office issued snow and ice weather warnings for Wednesday and Thursday, predicting a brutal blizzard will freeze the UK this week.
The warning covers large parts of Scotland, with another warning forecasting "dangerous" strong winds on the west coast.
The yellow warnings will remain in place until at least 9am on Thursday, it said.
It comes after long-range forecasts from the Met Office indicated a major Sudden Stratospheric Warming (SSW), causing a repeat of the 'Beast from the East' snowstorm.
The forecaster warned of further reduced visibility due to the thick fog leading to major travel disruptions.
The Met Office said the weather would bring "travel disruption and dangerous coastal conditions" and told commuters to expect slower journey times on buses, trains and planes.
People are also advised to take time on slippery icy surfaces walking on some could lead to injuries from slips.
The South East area had a warning earlier today, which expired at 11am this morning.
The Met Office said the East would see "freezing fog", with visibility reduced to just 50 to 100 metres in some places.
The Met Office Forecast:
Wednesday: Frosty with patchy dense freezing fog across central and southern areas, clearing to leave sunny spells. Very windy in the north with a band of heavy rain moving southeast across Scotland and Northern Ireland, turning to snow over the Highlands later.
Thursday: Cloud and drizzle in the south clearing, then dry with sunny spells. Occasional showers further north, heavy and wintry in far north, where still windy.
Outlook for Friday to Sunday: Dry with patchy cloud and sunny intervals, and pockets of overnight frost and fog. Strong winds across the north Friday along with some rain for the far northwest. Milder everywhere.
