As for this weekend, today will be sunny but cold, with a brisk wind.
'These have the potential to align into bands, bringing some significant accumulations.
They continued: "Not everyone will see snowfall, however 5-10cm is possible where showers do line up, with the greatest risk across eastern and southeastern counties".
The cold blast - dubbed the "beast from the east" - will see freezing temperatures, severe frost and disruptive accumulations of snow nationwide.
It says weather could potentially make a "dramatic few days".
Off a call with Met Office & ScotGovt Resilience Team.
It's due to be a cold week..
He said: "We haven't had temperatures that low in late February since 2013".
Ireland faces a week of icy winds and frigid temperatures as a vast high-pressure zone forces a freezing front from the Scandinavian and Russian Arctic westwards.
Lowest temperatures of 0 to -3 Celsius, coldest in Leinster and Ulster.
On Tuesday, the warning will be extended through north-east England and parts of Scotland, with snow showers expected across the United Kingdom on Wednesday. Clear we are going to have challenging weather over course of next week.
Public Health England said it is "critical" to keep an eye on anyone over 65, young children or people with heart or lung conditions.
"Remember keeping warm will help keep you well".
Heavy snow is expected to hit most of the United Kingdom next week as a cold blast of air known as "the Beast from the East" arrives from Russian Federation.