Owen Williams gave the Scarlets an early lead, but tries from Tommy Bowe and Robbie Diack combined with Ruan Pienaar's reliable boot have left Ulster 18-3 up at half time.
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Updates on Swansea City, Cardiff, Wrexham and Newport County.
There will be some light rain but it's mostly dry with sunny spells developing.
The UK has experienced a 4.4 magnitude earthquake. The epicentre was Cwmllynfell near Pontardawe in the Swansea Valley.