The Met Office has issued a warning for south Wales of very heavy rainfall over the next 24 hours. 30mm of rainfall is expected, with over 60mm on exposed higher ground.
Flooding has already been reported in parts of Pembrokeshire this morning and alerts have been issued for Carmarthenshire.
Drivers are being told to be aware of surface water on roads, and river flooding is possible.
By the end of the week the Brecon Beacons could see rainfall totals of over 150mm
Natural Resources Wales says The worst affected areas are likely to be across south Wales and across the Snowdonia mountain range in Gwynedd.
It is not expected to clear until Tuesday afternoon.
Please send us any of your photos of flooding to *firstname.lastname@example.org *
More top news
Charities in Wales say thousands of low-income families with disabled children could be missing out on grants, because of government cuts.
Tuesday will have a murky start with widespread fog, mist and low cloud.
A plan to secure the future of Port Talbot steelworks will be unveiled to staff on Wednesday, ITV News understands.