Met Éireann weather watcher, Gerry Murphy, reminds people that there is a status orange weather warning in place from now, 6pm.
The orange warning is in place right across the country, bar County Donegal, and remains in place until 11am tomorrow morning.
The Magheracloone man told Northern Sound temperatures recorded at the Ballyhaise weather centre last night were as low as 5.7 degrees.
He expects a similar dip tonight and says people should expect ice, black ice, freezing fog and generally difficult travelling conditions.