South Wales Police says the A465 is closed between Aberdulais and Resolven, after a serious crash.
Diversions are in place via the B4242.
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Central and northern areas could be forgiven for wondering what all the fuss is about, but rain edges into the south today!
All calm and quiet overnight, but southern areas could be in for a surprise tomorrow!
Scottish people living in Wales have been giving ITV News their opinions about the Scottish referendum vote on Friday.