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.
More top news
Cold with frost and fog inland,a little milder but breezy around the coasts!
UKIP's candidate in the Rhondda quits party claiming it's turned its back on the people it claims to represent
It follows an online campaign to give Iestyn Baldwin, from Bridgend "the best birthday ever".