Snow, sleet and storm force winds have caused disruption in Northern Ireland, leaving tens of thousands of homes without power and travel delays.
The Roads Service said more than 300 staff in 130 gritters were on stand-by to salt main roads last night.
Snow drifts of up to 15.7in (40cm) have been reported.
"Most routes have been salted three times overnight with snow ploughing necessary on many routes," a spokesman said.
The adverse weather conditions have also cast doubt over tonight's World Cup clash between Northern Ireland and Russia at Windsor Park.
Kick-off is due to take place at 7.45pm.
The Irish Football Association said it would make a decision after a pitch inspection and assessment of the South Belfast stadium later this morning.
If the match does not go ahead tonight, the IFA is looking at the possibility of playing it tomorrow.
The wintry conditions are now expected to last well into April with this month on track to become the coldest March since 1962.
A group of students from Wolverhampton who were stranded in extreme snow in Scotland for more than three days tell their story of survival.
Cold weather can pose a real health risk to older and disabled people, but everyone can gain from preparing their homes for the cold.