Road users are being advised to drive with caution tonight and tomorrow morning.
Widespread frost has been reported throughout the county, with black ice on higher grounds.
Tonight will be mostly dry and cold with fresh westerly winds. There is a risk of some sleet or snow showers, mainly on high ground in the north. Lows of minus 1 to plus 1 degrees with frost forming in places, and ice on untreated surfaces.
Friday will be cold and blustery with sunny spells and scattered showers. Highest temperatures of 3 to 6 degrees with fresh and gusty westerly winds. There is a risk of some sleet or snow showers in the morning, mainly on high ground