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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Showers this evening with heavier and more persistent rain arriving overnight. A wet start tomorrow but improving during the afternoon.
A mother from Neath has told how her teenage son collapsed and was left unconscious for five hours after taking a so-called legal high.
Two brothers from Cardiff are campaigning for their cousin's murder to be re-investigated, 76 years after she died.