Neighbours are being urged to look out for older, vulnerable people during the cold snap.
A forecast of extreme temperatures across the UK and Ireland has raised fears the elderly could be left housebound and unable to re-stock their food or medication supplies.
Those with personalised alarms or mobile phones have been warned to keep them charged so they can call for help if they get into difficulty.
Officials and charities both north and south of the Irish border have called on people to keep those living alone in mind as the mercury drops.
Ireland's Minister for Rural and Community Development Michael Ring suggested neighbours could visit the shops to get essentials for those in need.
He said: "Older people and those living alone are often most vulnerable to these cold snaps.
"It's important to look out for older people not only in isolated rural areas but also in built up urban areas. I urge people throughout the country to check in on your neighbours by phone or, if possible, in person. It is particularly important to check if people have enough food, fuel and medication."
The Public Health Agency (PHA) in Northern Ireland advised people to wear layers, eat well and ensure their house is properly heated.
The agency tweeted: "As temperatures begin to drop as the cold winds from Russia arrive in Northern Ireland PHA is advising everyone to look after themselves and their neighbours during the freeze."