WALES' environment agency has warned a period of "prolonged" rainfall could cause flooding in mid- and South Wales this weekend.

Natural Resources Wales (NRW) said people should be prepared for potential flooding amid weather warnings for heavy rain across the region.

“The predicted weather may cause flooding in south and mid areas of Wales so we’re advising people to keep up to date with flood warnings issued in their area via our website, which is updated every 15 minutes," NRW tactical manager Gary White said on Friday morning.

“We are working alongside our partners from the emergency services and local authorities to minimise the risk to communities.

“Flood water can be extremely dangerous, and I urge people not to attempt to walk or drive through it, unless instructed by the emergency services.”

The Met Office has issued a yellow weather warning for much of mid- and South Wales, with surface water and river flooding likely.

The heavy rain is predicted to fall from Friday morning and continue almost constantly until midday Sunday.

NRW said its emergency response workers would visit key sites to check defences were in good working order, and to make sure any drainage grids and screens were clear.

The weekend warning comes almost exactly one year since Wales was battered by Storm Dennis.