River Towy bursts banks after heavy rain across Wales
The River Towy has burst its banks in Carmarthen and high tides threaten further flooding elsewhere as bad weather continues to cause problems.
Three flood warnings - including for Carmarthen - and more than 20 flood alerts are in force around Wales.
Natural Resources Wales (NRW) warned high tides in coastal areas on Friday may bring more flooding.
The tides could be accompanied by strong winds of up to 80mph in some areas.
The banks of the Towy in Carmarthen burst on Thursday morning flooding a road but homes were not affected.
Carmarthenshire council is holding an emergency planning meeting ahead of tides on Friday and Saturday which are expected to be the highest in two years.
Spokesman Ron Cant said the local authority had "invested millions" in recent years in strengthening weak spots in the river's flood protection works.
He said: "This type of weather over the next few days will probably test other areas and challenge us.
"We can only react to what happens. You can't protect everything. We know the weak spots and they have been addressed over the last few years."
He added that the high tides on Friday were likely to be made worse by expected stormy weather.
NRW said it expects tides early on Friday morning to be some of the highest in nearly two decades.
Its officers said they are keeping a close eye on coastal stretches around the city of Newport, in particular the Crindau area, at Barmouth, Borth, Carmarthen Bay and Haverfordwest on the west coast of Wales, and the north Wales coast from Kinmel Bay to the Dee estuary.
The high tide is expected at Milford Haven at about 07:20 GMT on Friday, reaching Newport by 08:15, Barmouth in Gwynedd at 09:20 and Flintshire by midday.
NRW said it was possible that some severe flood warnings may be issued - the highest level of flood alert, warning of danger to life.
"We have already been speaking with our partners from the emergency services and all the local authorities which might be affected so they can put their plans into action," said a spokesperson for NRW.
The agency said it was using the window of relatively calm weather on Thursday to check that storms drains and other flood defences were clear.
Spokesman Jeremy Parr told Radio Wales said: "We're going to make sure all our defences are working properly, to make sure that all the grids and grilles on defences are not blocked so that the water can get out and escape to try and lessen those impacts.
The NRW is also warning people in coastal communities not to walk or drive too close to the seafront to look at waves which are expected to be large enough to overtop defences.
Mr Parr added: "We're urging people to not go out and have a look at this - it can be tempting - and certainly not drive in any of those areas tomorrow morning.
"If it does come through as the predictions show then it perhaps could be quite bad."
The high tides come as tThe Met Office is warning of strong winds in coastal areas on Friday bringing large waves and increasing flooding risks.
Its weather warning has been updated to say people should expect winds of up to 80mph along the coast.
On Wednesday, police in Aberystwyth arrested an early-morning swimmer who had sparked a rescue alert after getting into difficulties in 15ft (4.5m) waves.
The man was later issued with a £90 fixed penalty for being drunk and disorderly.
With many people returning to work roads are largely clear of disruption, with the M48 Severn Bridge reopened to high-sided vehicles.
However, flooding closed the A4042 between the A40 and the A465 Heads Of The Valleys Road at the Hardwick roundabout, Abergavenny.
The A472 reopened following flooding between A4042 Usk Road and Cefn Mawr Lane.
South Wales fire service said it was called to a few flooding incidents in Monmouth and Raglan overnight.
Mid and West Wales fire service said crews had been helping to pump out the cellar of the Halfway Hotel in Llanelli.