The Met Office has issued a yellow warning for Northern Ireland, with Storm Caroline expected to brings snow, ice and winds of up to 70mph.
People travelling by road, rail, air and ferry have been warned of potential delays and service cancellations.
There may also be short-term power outages.
The organisation's Chief Forecaster said winds will ease as Thursday progresses, but snow showers will become more frequent and heavier.
Between one and four centimetres of snow will fall in higher parts of Northern Ireland
The snowfall is set to continue into Friday, when the Met Office estimate as much as 10-20cm could be possible, particularly around the Sperrins and Glens of Antrim, bringing slippery surfaces and potential travel delays.