The Met Office has issued a yellow "be aware" warning of ice for Denbighshire, Flintshire, Powys, Wrexham and Monmouthshire.
It says there could be difficult driving conditions in places.
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Farmer Gareth Wyn Jones is hoping for a festive online hit with footage of sheepdog Cap rounding up sheep.
It is expected to remain wet and windy for the rest of today, overnight and tomorrow. Conditions improving on Christmas Eve
In this clip from 1959 Father Christmas gets some very practical requests for Christmas Day.