North Wales Police are appealing to anyone who has left a flooded property in the Garford Road area of Rhyl to stay with relatives or friends to contact them immediately.
Emergency service are about to begin a search of affected properties in the area in an effort to account for all residents.
The number to call is 01492 518383.
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Swansea relieved the pressure on under-fire manager Bob Bradley with an emphatic 3-0 home victory over fellow strugglers Sunderland.
Sol Bamba was sent off after losing his cool but Cardiff hung on to claim a deserved 1-1 draw at Ipswich.
Today's rain will soon clear south-eastwards to leave a largely dry night with some long clear spells.