Elderly people with vaccine appointments have been warned not to brave dangerous conditions caused by a “rash of snow showers” set to sweep the UK in the coming days.

Age UK has urged people to look out for elderly relatives as Tuesday night is expected to be the coldest of the winter, with lows of minus 18C forecast in the Scottish Highlands.

This follows the record set overnight on Monday, when minus 16.7C was recorded in the region.

Met Office meteorologist Clare Nasir said “temperatures will plummet wherever you are” on Wednesday, and “strong winds” and snow will be “disruptive across many areas” in the UK.

Ms Nasir added: “Through Wednesday morning, we’ll see a rash of snow showers, but subtle changes through the day, the winds will lose their strength as the snow showers become more confined to the east of England.

“Further west, we’ll see some brighter skies and sunshine through the day but we will see more showers come in through the far north-east of Scotland on Thursday after another severe frost and bitter start to the day.”

Wednesday’s daytime temperatures are forecast to range from -1C to 2C in London and Cardiff, and for Edinburgh from -5C to 0C.

Yellow weather warnings for areas where snow and ice could cause travel disruption cover much of Northern Ireland until 11am on Wednesday, and the eastern half of the UK mainland until midnight.

This warning remains in place throughout Thursday and Friday for the north-eastern edges of England and Scotland.

Director of Age UK Caroline Abrahams has warned elderly people with vaccine appointments not to attempt travelling through treacherous conditions.

She said: “Rather than battling the elements and putting health at risk, it would be better to call your GP to see what the alternative vaccination arrangements are being made locally.

“It’s important to remember that Covid-19 vaccination is not a one-off opportunity, if for any reason you can’t take the first appointment you’re offered there will be other opportunities later on, possibly in a range of nearby settings.”

Cold temperatures increase blood pressure, which can trigger heart attacks and strokes in elderly people, and breathing in chilly air can increase the impact of illnesses like flu and pneumonia.

The charity’s advice for those heading out on essential journeys includes planning ahead to avoid dangerous routes, wrapping up warm, and helping grandparents with shopping so they can stay indoors.

Norfolk Police has also warned people not to travel in blizzard-like conditions, adding that many roads have fallen victim to snowdrifts.

Officers attended a number of minor road traffic collisions on Monday, when Storm Darcy was ravaging the UK, and police in King’s Lynn said that a lorry got stuck in a snowdrift and had to be towed out by farmers.

Vaccination centres in Ipswich and Bury St Edmunds in Suffolk and Clacton on Sea and Colchester in Essex also remained closed on Tuesday due to the severe weather.