Goals by Nathan Dyer and Michu have put Swansea City in a magnificent position as the two sides enter half-time.
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It's judgement day at the Millennium Stadium as Cardiff Blues take on the Ospreys and the Newport Gwent Dragons face the Scarlets.
Showers expected throughout the day especially in the north. Drier and brighter elsewhere but cooler than in recent days.
Most places will become dry overnight, although it will remain generally cloudy with patches of hill fog.