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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Well a fabulous day today has ended on a spectacularly soggy note for some! Heavy rain, hail and thunder will work northwards overnight!
The Talyllyn runs from Tywyn, near Aberdovey, for more than seven miles to two villages in the south Gwynedd countryside.
Homes in parts of Tonypandy and Llwynypia are without water this evening due to a burst water main at Cilfynydd.