Motorists are advised to exercise extreme caution.
The Department for Infrastructure tweeted: "Icy conditions tonight. Salting is planned on Main routes likely to be affected. Take care driving."
Snow and sleet are expected to make an appearance in the rest of Northern Ireland over the next few days as the Met Office issued a yellow warning of ice for Northern Ireland.
There has been a noticeable drop in temperature and wintry showers are expected later on Thursday and overnight into Friday.
The Met Office said there will be hail and thunder in the north and west with the potential for snow and sleet on higher grounds before moving on to lower levels later.
On Friday more wintry showers are expected creating frost and ice patches with the maximum temperature dropping to 5 degrees.
Over the weekend some sunshine is expected to break through but overnight there will be widespread fog perhaps leading to some freezing fog patches.
The Met Office chief forecaster said: "A cold northwesterly airstream will bring heavy showers or rain, sleet, snow and hail through this period.
"Clear spells in between will allow temperatures to fall close to or below freezing - hence the likelihood of some ice. "
The ice warning is valid from Thursday November 17, 6pm until Friday, November 18 at 10am.
Weather presenter Barra Best told BBC NI: "As temperatures fell close to freezing after sunset, the showers quickly turned wintry over hills and mountains. Lower level areas have also reported sleet and snow falling.
"The Met Office ice warning is in place across Northern Ireland from 1800 GMT on Thursday until 1000 GMT on Friday. It warns of ice forming primarily on untreated surfaces, but also warns of up to several cms of snow accumulating on the hills.
"More than six cms of snow is forecast for some higher areas, with slush conditions for lower levels."