The UK has been struck by extreme weather over the past weeks, with devastating flooding striking the north. This week, the skies have cleared but the reprieve has been met with icy temperatures.
Public Health England (PHE) has issued a cold weather alert until midday on Wednesday.
The alert is in place for the northeast, northwest and Yorkshire and Humber.
Dr Emer O’Connell, Consultant in Public Health at Public Health England, said: “Older people and those with heart and lung problems are at risk of getting sick in cold weather.”
She urged residents to look out for one another as the temperatures drop.
Dr O’Connell said: “Keep an eye out for those who may need help staying warm, ensure they wear lots of thin layers and have everything they need.
“Below 18 degrees, changes to the body mean that the risk of strokes, heart attacks and chest infections increase so heating homes to this temperature is particularly important to stay well.”
The warnings come as regions in rural Scotland plummeted to almost -10C in places in the early hours of Tuesday morning.
Braemar, Aberdeenshire, recorded -9.9C, the coldest yet this season.
In Northern Ireland, they dipped to -5.1C (22.8F) in Katesbridge, County Down.
Wales will avoid the worst of the cold but the rest of the nation will be very chilly.
You can see the map above for the ‘feels like’ temperature where you live on Tuesday.
Met Office Chief Meteorologist, Steve Ramsdale, said: “After a very wet period for parts of the UK the weather is now turning much quieter for a few days.
“With these quieter conditions, night time temperatures will fall away with more widespread frosts than seen recently despite daytime temperatures remaining fairly similar.
“Tuesday morning in particular looks to be cold across much of England.”
By Thursday, clouds will have smothered the UK again, warming temperatures and bringing back the rain.
Large parts of the country remain flooded, with experts warning woes could continue.
On Tuesday, the Environment Agency issued 28 flood warnings and 65 flood alerts.
Sunday saw the rivers Severn and Avon burst their banks, leaving properties waterlogged in Gloucestershire and Worcestershire.
The worst flooding is now expected to be around the Severn, north of Gloucester, areas around the Trent and fens in Lincolnshire.
There is also more chaos for residents living near the River Don, as villagers in Fishlake, near Doncaster, have been told not to return home because of standing water and impassable roads.