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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It is going to stay fine and dry through the night with light winds.
It is going to stay fine and dry throughout.
There have been four deaths on the M4 in just the last eight days following crashes between Swansea and Newport.