Dyfed Powys Police say they have had reports from all over west Wales about flooding on roads and in houses.
A spokesperson for the police said they had been 'inundated' with received calls from areas including Aberystwyth, Carmarthen and Pembrokeshire.
He advised people to stay inside and avoid driving due to flood water gathering on both minor and major roads.
Traffic Wales says no roads as yet are closed due to the flooding. To check for updates visit the Traffic Wales website.
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Cloudy with rain and strong winds, local gales along exposed coasts. Rain persistent across western hills, and becoming heavy later.
It will be cloudy with hill fog and mild overnight with increasing winds, with gales around southwestern coasts.