North Wales Fire Service says that it received 11 calls from people whose properties were vulnerable to flooding. The majority of those calls were from the Dolgellau area.
Environment Agency Wales has issued flood alerts for Bridgend, Vale of Glamorgan, Rhondda Cynon Taf, Carmarthenshire and Pembrokeshire.
"More than 300 calls" were received by Mid & West Wales Fire Service between 7pm last night and 2am this morning about the flooding. The service says the worst affected areas were Kidwelly, North Gower, Narberth, Solva and Pembrokeshire.
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.