A level 2 cold alert has been issued amid freezing temps while flights could be cancelled as a thick fog blankets parts of Britain.
Temps in England are expected to plummet to a chilly low of -4C over five days this week.
Fog is expected to blanket much of the southern England on Tuesday nightCredit: Alamy
The Met Office has issued a yellow weather warningCredit: Terry Harris
The UK Health Security Agency (UKHSA) issued the alert on Tuesday while asking people to “look out for those most at risk” from the effects of cold weather.
Meanwhile, the Met Office has announced a yellow weather warning for large parts of the Midlands, East Wales, and South East England as they face being hit by thick fog.
The warning will be in place from 10pm tonight and last until midday Wednesday.
Forecasters warned that visibility could drop to “lower than 100 metres” at times and lead to major travel disruption.
The alert said: “Fog patches are expected to form during Tuesday night, becoming dense and freezing in places by dawn on Wednesday, particularly in river valleys with visibility less than 100 metres at times.
“Fog will thin slowly later Wednesday morning, although a few patches may persist into the afternoon over the south-west Midlands.”
Forecasters said this could see “slower journey times” to bus and train services and “delays or cancellations to flights”.
With temps set to plummet, people are being urged to keep an eye on the most vulnerable.
Agostinho Sousa, a UKHSA consultant, said: “As we continue to experience very low temperatures this winter it’s important to remember to check on those who are more vulnerable to cold weather, such as elderly or frail friends and family, especially if they live alone or with a serious illness.”
She urged the “most vulnerable” to keep their homes heated and advised people wear shoes with good grip when outside.
Met Office Deputy Chief Meteorologist Dan Rudman said: “Temperatures in central and southern England are expected to trend downwards from Thursday, with overnight minimum temperatures possibly getting to -4 °C in some rural areas, but widespread below-freezing conditions elsewhere overnight in the following days.
“This will result in some harsh frosts and possible freezing fog in some places.
“Temperatures will stay subdued through the next few days from Thursday in the alerted areas, with highs likely to remain in the mid-to-low single figures through the weekend, especially in places where any fog or low cloud lingers throughout the day.”
A gigantic blanket of fog is expected to hit East and West Midlands, London, East Wales, the South East and East of England with sunny conditions expected for southern and central areas by Wednesday midday.
Temps will near average before the frost and fog return in the evening.
Northern areas will see strong gusts while rain and drizzle is expected in Scotland and Northern Ireland on Tuesday night.
Southern areas will see fog and low cloud cover throughout the week and into Saturday while the North of England can expect milder weather with cloud, rain and stronger winds at first.
Temps are expected to plummet in many parts of EnglandCredit: Alamy
People are being asked to check in on loved onesCredit: Mercury