- indicating a threat to life - will be in force from 3pm on December 26.
It will apply to parts of south Wales and across southern England, with gusts expected to reach up to 70mph in coastal areas.
It is the second named storm of the season.
The weather warning comes after thousands Brits - already hit with a tough year after a string of coronavirus lockdowns - were confronted with devastating flooding after a deluge of rain overnight.
Shocking photographs showed towns submerged as the flood waters seeped into homes and businesses in Norfolk - with emergency services declaring a major incident.
The BBC reported the South Wales Fire and Rescue Service received 500 calls for help on Wednesday with 300 just in six hours.
Pictures showed the aftermath of a landslide that began on a steep slope above a car park in Penarth, south Wales at around 6pm on Wednesday.
Cars were seen surrounded by branches, mud, and other debris, but there were no reports of any injuries.
Northamptonshire Fire and Rescue Service said they had handled more than 250 flood calls, with several properties inundated and multiple people rescued from their stranded vehicles.
In Nottingham, police said emergency services had been called to a report of a landslide near some homes near a former quarry at 11.40pm on Wednesday.
The force said a "small number" of properties had been evacuated, and police, fire, and ambulance services, along with Mansfield District Council officials, were at the scene at Bank End Close in Mansfield to conduct safety assessments.
Charlotte Taylor, of Topcroft, Norfolk, tweeted pictures of her flooded home - including a ruined box of Christmas crackers - in the early hours of this morning.
"If there is a photo that sums up my Christmas this is it," she wrote.
"Mum of three all with Covid stuck indoors literally watching the house flood."
Flood defences have been installed in Ironbridge, Shropshire, ahead of Storm Bella Credit: PA:Press Association A family ride through the floodwater at Orton as the River Nene burst its banks in Peterborough, Cambridgeshire Credit: Paul Marriott An ambulance is seen in the flood waters in Stowmarket Credit: Stephen Huntley/HVC A cyclist tries to get through the flood waters in Suffolk Credit: Stephen Huntley/HVC Several people had cars and vans stranded after flooding on roads after rivers burst their banks after Credit: Stephen Huntley/HVC An aerial photograph shows Alconbury in Cambridgeshire on Christmas Eve morning Credit: GEOFF ROBINSON. Christmas crackers ruined by flooding in Topcroft, Norfolk Credit: Charlotte Taylor Marilyn Squires during the Christmas Eve clear up after her house in Dinas Powys, South Wales Credit: Huw Evans Picture Agency Sally Walsh during the Christmas Eve clean up in Dinas Powys, South Wales Credit: Huw Evans Picture Agency Mum-of-three Charlotte Taylor said the pictures of her flooded him 'summed up her Christmas' Credit: Charlotte Taylor A woman wades through floodwaters in Tewkesbury Credit: © Jack Boskett Queues of traffic on a flooded road in Tewkesbury Credit: © Jack Boskett Bury, Huntingdon flooded after the River Lode burst its banks Credit: � Terry Harris A landslide hit a car park in Penarth, Wales after heavy rain Credit: Huw Evans Picture Agency Mud and tree branches seen in the aftermath of the landslide Credit: Huw Evans Picture Agency Worse weather is yet to come on December 26 Credit: MET Office The Environment Agency issued more than 107 flood warnings as of Thursday morning, including across Devon, the West Midlands, and 20 related to the River Severn along the Welsh border.
Other affected areas include Norfolk, Lincolnshire, the East Midlands, and along parts of the Great River Ouse.
A further 164 flood alerts, which warn of possible flooding and urge preparedness, have also been issued.
Eight flood warnings and nine flood alerts are also in place across Wales.
The warnings are concentrated mostly along the south coast, near Cardiff and Tenby, though include one for areas surrounding the River Dee near Wrexham.
After a difficult year, Brits were also faced with flooded homes and a mammoth cleaning up effort the day before Christmas as the floods hit areas of Gloucestershire, Cambridgeshire, and East Anglia.
In Gloucester, a pub that had been closed for several months because of coronavirus lockdown has now had to close again because of flooding.
The Toby Carvery at Over, near Gloucester, had reopened July after the first lockdown but was forced to close again in November.
It has now had to cancel Christmas Day bookings as well as plans to serve takeaways from Boxing Day, when Gloucestershire is set to move into Tier 3.
Also flooded was the nearby Over Farm shop.
FLOODED HOMES In a video message, Rees Keene, a partner in the business, said: "I'm at the back of the shop and I've never seen anything like this.
"We had to close the road ourselves and every time a car drives through it is like a foot waterfall. Happy 2020."
He added that police were on site to offer assistance.
Gloucestershire residents also took to social media to vent their frustration after the River Severn flooded.
"As if today/ this week wasn't already full of enough bad news. My hometown is now flooded," Lauren Wilden wrote on twitter.
Liam Ball added: "Minor flooding on The River Severn this morning at Leighton and Ironbridge.
"Its forecast to rise further through the night and peak sometime tomorrow."
Patrick Lloyd, 27, from Peterborough, said he woke up to find much of his home had been submerged in water, causing thousands of pounds worth of damage.
He added that he had to help rescue an elderly neighbour who had become trapped without power.
Mr Lloyd said the 86-year-old woman had eventually been taken to hospital after spending around 50 minutes in the "freezing" floodwater.
"Luckily a bloke driving by saw her and got out and helped us with her," he said.
Flooding hit Cambridgeshire after the Great River Ouse burst its banks Credit: GEOFF ROBINSON. The area around Caldicot Castle, Monmouthshire was flooded Credit: Matthew Horwood Flooding on a residential street in Alconbury Weston, Huntingdonshire Credit: Paul Marriott A minibus stuck in floodwater in Alconbury Weston Credit: Paul Marriott A police officer empties his wellies in Alconbury Weston Credit: Paul Marriott The village has been hit by flooding following heavy rains Credit: Paul Marriott Heavy snowfall this morning in County Durham Credit: Jordan Crosby Forecasts suggest this year will see the coldest Christmas Day for five years Credit: Jordan Crosby "We had to get the fire service out to get her on to a board and we lifted her out for an ambulance
"We were worried about hypothermia, she spent a night in hospital. No idea if she made it or not."
Alex Burkill, a meteorologist for the Met Office, said: "There's been a lot of wet weather around.
"We've had a heavy rain across much of England and Wales, particularly southern parts of Wales, but also further east.
"Most places in England and Wales have been really wet and we've seen strengthening winds too, there have been some gales in exposed parts, so quite unpleasant really."
Mr Burkill added that the rainfall would cease overnight into Christmas Eve.
"The wet weather we've got over us at the moment that's all going to clear away towards the south-east as we go through the night.
"So for Christmas Eve we're going to have lots of fine weather around, with lots of sunshine and a cold northerly flow."
Forecasts also suggest Britain is set to see the coldest Christmas Day in five years , with some snow expected in parts and ice warnings issued.
Pictures from County Durham this morning showed heavy snowfall, with local temperatures currently at around 3C.
Flooding after heavy rainfall in Bury, Huntingdon Credit: � Terry Harris A police officer wades through floodwaters in Alconbury Weston Credit: Paul Marriott The entrance to a flooded race track in Worcester Credit: SWNS:South West News Service Aerial view of a flooded field in Worcester Credit: SWNS:South West News Service Joggers out amid flooding in Cambridgeshire Credit: � Terry Harris Festive swimmers in Swansea undeterred by flooding along Wales's southern coast Credit: Alamy Live News Emergency workers at a flooded home in Cambridgeshire Credit: Paul Marriott machibet777.com