Sarah Bridge, 55, compared Storm Dennis to a tornado and said water had flooded her home in Pontrilas in Herefordshire despite specialist flood doors, reaching her knees.
“It’s heartbreaking,” she said. “The kitchen is completely flooded, I can hear things floating about downstairs.”
The red rain warning in south Wales, which lasted until 11:00 GMT, advised residents to “take action” to keep safe from dangerous weather and avoid travel.
Wind gusts reached 91mph on Saturday, according to the Met Office, while 142mm of rainfall was recorded at the Cray Reservoir in the Brecon Beacons National Park in Wales.
Jessica, who is on holiday with her family in Crickhowell, Powys, to celebrate her mother’s 60th birthday, told BBC Radio 5 Live that firefighters woke them at 04:00 GMT to tell them they were being evacuated because the River Usk had burst its banks.
But water quickly came flooding into their holiday home, forcing them upstairs and stalling their evacuation.
“The door of our house burst open and water came flooding in right up to the top of the stairs which was quite nerve wracking at the time,” she said.
She added: “It’s well over the front door of the house, it’s flooded all the way up to the ceiling.”
In Pontypridd, bar worker Jack Jones said he had to leave work on Saturday evening as water from the River Taff entered the bar.
“It came from nowhere,” he said. “To come down this morning and see it like this is quite shocking.”
In York, the Environment Agency has predicted the River Ouse could come close to record levels seen in 2000.
Properties were flooded in Tenbury Wells, Worcestershire, on Sunday morning – and residents were urged to take “extreme care” by the area’s Environment Agency manager.
Across the UK road, rail and air travellers also face disruption.
About 170 flights were cancelled as of Sunday morning, affecting at least 25,000 passengers.
The storm has caused disruption at Edinburgh, Glasgow, Newcastle, Southend, Stansted, Heathrow and Gatwick airports over the weekend.
Rail services have been suspended across south Wales, and in parts of England and Scotland, according to National Rail.
Highways England said strong winds had closed part of the M48 Severn Bridge eastbound and the QEII bridge at the Dartford Crossing, while flooding closed A-roads in South Yorkshire, Herefordshire, Derbyshire, Nottinghamshire and Gloucestershire.