Flood problems have hit several areas of Wales, with roads shut, homes pumped out and campers at the Wakestock music festival relocated after heavy rain.
Three flood alerts are in force on the rivers Conwy and Clwyd, and Swansea Bay and Gower, with up to 4in (10cm) of rain expected in areas.
The A55 was closed at Abergwyngregyn near Bangor, leading to severe delays.
The M50 into south Wales was also partly closed from the M5 junction.
The Highways Agency says floodwater prompted it to close a stretch of the M50 motorway heading from the M5 to junction two, Tewkesbury to Ross-on-Wye. Officials expected it to reopen on Friday evening.
As river levels across Wales continue to rise, Environment Agency officers were checking that flood defences were working.
In Gwynedd, North Wales Fire and Rescue was called to help with localised flooding at properties in Pwllheli, Llaniestyn, Aberdaron and Botwnnog.
In Botwnnog Gwyn Richards was trying to stop more water entering the home of his grandmother, Nancy Pritchard.
"We're bailing out as fast as we can but if it carries on like this I can't see what we can do," he said.
Mrs Pritchard, who is 89, was trying to mop up the water inside her home.
"I've had this before but this is the first time it's come through the walls. The river rose so quickly there wasn't a chance to do anything," she added.
Gwyneth Evans said it was the worst she had seen since 1993.
"Since then the council has put in kerbs, and we're hopeful it'll keep the water out of the house this time," she said.
It comes as the Wakestock music and wakeboarding festival got under way at Abersoch on the Llyn peninsula, with 15,000 people booked for the weekend.
Organisers held a site meeting on Friday morning, and despite torrential downpours, said the weekend music and Wakeboarding event would go ahead.
"The water levels are now dropping and we have also got three big sucking machines working in the campsite to help speed that up," the event's team posted on Facebook on Friday.
"On the whole spirits seem to be high. Our campsite management team are helping people relocate from the really wet areas to more solid ground and the event management, medical, safety and police teams are all meeting regularly to work out our priorities."
North Wales Fire and Rescue Service were called to Llanddulas in Conwy to deal with flooding there.
Eye witness Danny Darbey said: "Llandulas is a beach village. The higher part is okay, but the caravan park in the lower village is cut off."
Organisers of the Llangollen International Eisteddfod urged people to make alternative travel arrangements if possible, due to heavy rain limiting spaces in the car park.
Uncle Sam's American Circus called in firefighters at Bridgend because of flooding at the entrance to its site in Laleston Road.
South Wales Fire and Rescue Service said there was nowhere to pump the water as the whole area was saturated and the area would be re-examined later on Friday.
The Environment Agency said continuing "very heavy downpours" across Wales through the afternoon and into the evening were of particular concern.
It said the heavier rain would fall in Powys, Ceredigion, Conwy, Gwynedd, Denbighshire, Flintshire and Wrexham, which could cause "major disruption and significant flooding".
BBC Wales weather presenter Sue Charles said the Met Office had issued an amber warning because of the risk of localised flooding.
"More than 10mm of rain has fallen in Hawarden and Presteigne in the last five hours," she said.
"Heavy rain along the border counties is now moving westwards."
North Wales Police warned people to only venture out if journey was absolutely necessary, to drive with extra care and take a mobile phone if possible.
The fresh rain comes as some villages in Ceredigion still deal with the damage caused by flooding on 9 June, where some places saw 5ft (1.5m) of water with record high river levels in places.
The Prince of Wales and the Duchess of Cornwall will visit some of those affected during their summer tour of Wales next week.
Last month became the wettest June on record, with more than 186mm (7in) of rain falling - more than double the average.
The bad weather has continued since, with blame being given to the jet stream - strong winds 30,000 feet high in the atmosphere - which remains out of its usual place.
For the latest on flood alerts and warnings go to the Environment Agency website or call Floodline on 0845 988 1188.