Freezing temperatures are set to remain across Northern Ireland this week, according to forecasters.
The lowest temperature of the year so far, minus 9C, was recorded in Katesbridge, Co Down in the early hours of Monday.
Met Office weather warnings for ice and fog remain in place until 10am on Tuesday.
The sub-zero temperatures are set to continue until Thursday.
Travel has been affected by the weather, with a number of flights from London cancelled on Monday.
The Met Office has forecast another cold day across Northern Ireland on Tuesday despite spells of weak winter sunshine, and scattered wintry showers.
Wednesday and Thursday are expected to see occasional rain, sleet and snow showers.
Police have urged motorists to take extra caution when driving due to icy conditions in some areas.
“Please reduce your speed and drive to suit the conditions,” they added.
