A Met Office yellow warning is place across parts of Northern Ireland for snow and ice.
Forecasters say a spell of cold weather is expected to bring snowy showers and may lead to some minor travel disruption.
The alert began on Tuesday evening and runs until 9am on Wednesday and affects counties Tyrone, Londonderry, Antrim, and Down.
In a further warning for Thursday and Friday, the Met Office says "heavy snow has the potential to cause significant disruption".
It runs from 7am on Thursday to 2pm on Friday and covers all counties of Northern Ireland.
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