Many schools across the north west are to remain closed on Wednesday as snow and ice continues to make travel treacherous.
Almost 700 schools in Northern Ireland were shut on Tuesday because of the weather.
Roads Service said there was widespread ice on the roads on Wednesday morning, and in some areas it is covered by fresh snow.
All routes are described as passable with care.
City of Derry Airport is open and is operating normally.
Derry City Council said it has deployed additional resources to clear some paths in and around the city centre.
Cemeteries and council playparks are closed because of the bad weather.
Civic amenity sites at Park, Eglinton and Brandywell are currently closed. The sites at Strathfoyle and Claudy are also shut, but are expected to open on Wednesday afternoon.
The North West Regional College in Derry, Limavady and Strabane is open, but all evening classes from 1700 GMT have been cancelled.