Met Eireann has said that they expect the bitterly cold conditions will persist for the week, with milder weather gradually approaching from the southwest near Christmas.
There will be scattered snow showers each day, with some persistent an heavy snow possibly on Tuesday.
Monday night will be extremely cold with lowest temperatures between -5 and -10, possibly even lower over snow fields. There will be a few snow showers, mainly in coastal areas, and winds will be light.
Freezing fog will form in some areas as well. It will stay very cold on Tuesday, Wednesday and Thursday with afternoon temperatures staying below freezing in many areas and night time temperatures falling between -5 and -12 degrees in slack winds with a continuing risk of freezing fog.
There will be scattered snow showers with coastal areas most at risk. On Tuesday, a band of snow will give more prolonged and heavy snowfall, with eastern and southeastern areas most at risk. It will probably stay cold on Friday, Christmas Eve, but milder weather with rain and wind is approaching from the southwest, however it is not certain yet whether this milder weather will spread countrywide on Christmas day or that it will stay cold for the day.