Britons have been warned to brace for strengthening winds and lashing rain as Storm Franklin moves in overnight.
The Met Office has issued an amber warning for wind which could cause a “risk to life” in Northern Ireland until 7am, while a milder yellow wind warning covers England, Wales and south-western Scotland from midday until 1pm.
Environment agencies have issued hundreds of alerts for flooding across the UK, including two rare “severe” warnings where rainfall could also pose a “danger to life” for communities along the River Mersey in Greater Manchester.
This comes after huge waves were seen crashing onto coastal areas, homes were destroyed by strong winds, and emergency services deployed flood defences along swelling riverbanks on Sunday.
The River Don burst its banks in the Sprotbrough area of Doncaster in South Yorkshire on Sunday night, and police have warned people to stay away from dangerous “fast flowing” water.
South Yorkshire Police said: “We ask people to remain away from the area of Sprotbrough Falls and Sprotbrough Lock in Doncaster, after the River Don burst its banks in this location earlier this evening.
“Many of the footpaths in this area are presently underwater.
“The water is fast flowing and poses a risk to people attempting to wade through it.
“Members of the public are being asked to remain away from the area at this time for their own safety. Thank you.”
The River Severn has also been threatening to burst its banks, with water creeping towards homes in Ironbridge, Shropshire, and emergency teams have erected flood barriers along some sections of the waterway.
In Derby, firefighters from three locations were called to Wilson Street at 4.15pm after a roof blew off a terraced house, causing damage to five other properties.
Colossal waves have been captured engulfing Newhaven lighthouse in West Quay, East Sussex, and Porthcawl Lighthouse in Bridgend, Wales.
Met Office meteorologist Becky Mitchell said last week marked the first time three named storms have been recorded within seven days since the storm-naming system began in 2015, with Dudley, Eunice and Franklin.
She added that there will “definitely be some impact” from Storm Franklin on Monday but it is not expected to be “as severe” as Eunice because the strongest winds will be confined to the coast.
Gusts of 60-70mph are predicted to hit inland Northern Ireland in the early hours of Monday morning, while 80mph speeds are expected on the coast.
Gales of up to 60mph are expected to sweep the rest of the nation.
As of 10pm on Sunday, the Environment Agency had issued two “severe” flood warnings in Didsbury and Northenden in the North West.
Katharine Smith, flood duty manager at the Environment Agency, urged people to “stay away from swollen rivers” while teams deploy temporary barriers and pumps on the river.
“We advise people to stay away from swollen rivers and not to drive through flood water as just 30cm of flowing water is enough to move your car,” she said.
“Residents close to the River Mersey are being warned to take immediate action and prepare for property flooding.”
Manchester City Council began evacuating affected residents on Sunday afternoon in advance of the rising waters.
On Friday, Storm Eunice caused what energy providers believe was a record national outage over a 24-hour period, with around 1.4 million homes losing power.
Ross Easton, director of external affairs at the Energy Networks Association (ENA), said 56,000 people were still without power on Sunday afternoon, and Storm Franklin will hamper recovery efforts on Monday.
Mr Easton told PA: “We’re still making pretty good progress in terms of reconnections, but it’s certainly being hampered by the high winds.”
Giving advice to those facing a fourth day without power, he added: “First and foremost, check on friends, family, and neighbours to make sure they’re safe and well, and if you have any concerns or need extra support, call your local network operator.”
The Environment Agency has also issued 183 warnings where “flooding is likely” for locations mainly in the north and west of England, and 172 alerts where “flooding is possible” for the north-western half of the UK, London and the south coast.
Some 18 flood warnings and seven alerts have been issued across the Scottish Borders, Ayrshire, Orkney and the Western Isles by the Scottish Environment Protection Agency (Sepa).
Natural Resources Wales has issued 26 flood warnings and 47 alerts covering much of the country.