The country faces a “timeline of different hazards” this week as Storm Christoph moves in, a weather forecaster has said.
Weather warnings for heavy rain are in force across the UK, but the unsettled conditions could also bring significant flooding, high winds and snowfall as the storm engulfs the country through the middle of the week.
Met Office spokesman Oli Claydon said that rain is “initially” the main concern but the picture will change as low pressure could introduce colder air.
He explained: “As we go through the week and the low pressure that is bringing these fronts of rainfall that are persistent and heavy over the next few days … as that low pressure moves east and out into the North Sea, the winds will become a thing really later in the week.
“Also as the low pressure moves away it pulls down a north-westerly airflow which brings much colder air across the UK again which then presents a further risk of snow.”
Mr Claydon described the situation as “a timeline of different hazards as we go through the week but the first hazard is certainly of rain and that’s reflected in the warnings at the moment”.
Public Health England (PHE) has issued a cold weather alert from “first thing” on Thursday until 9am on January 25 for the North East, North West and Yorkshire and the Humber.
The agency said the risk of flooding will amplify the public health risks of the severe cold weather.
Dr Owen Landeg, a principal environmental public health scientist at PHE, urged the public to check on elderly or frail neighbours, reminding them to heat their home to at least 18C (64.4F).
The Met Office’s most serious weather warning – amber for rain – has been in place across parts of the Midlands and northern England since Tuesday morning, alongside less serious yellow warnings for rain across Wales, Northern Ireland, northern England and southern Scotland.
Its chief meteorologist Neil Armstrong said: “Parts of central and northern England and Wales could potentially see a month’s rain in just 48 hours or so, with up to 200mm possible over higher ground, presenting a real flooding threat.”
The highest rainfall recorded overnight was in Aberllefenni, west Wales, where 35.4mm fell between midnight and 8am on Tuesday.
Of the areas in the amber warning zone, Bolton in Greater Manchester has seen the most rain so far, with 24.4mm over the same period.
By Wednesday, the yellow warnings for rain will stretch south to additionally cover all of England, all of which remain in place until midday on Thursday, alongside the more serious amber warning in central England.
Eastern Scotland is also facing a yellow warning for snow and from Wednesday afternoon through to Thursday lunchtime, with the threat of travel delays, power cuts and rural communities being isolated.
The Environment Agency has warned of “significant flooding” risks across northern, central and eastern England, with flood defences being erected in some areas to protect communities over the coming days.
The National Flood Response Centre is coordinating the response from Government but no meeting of the Cobra emergency committee has yet been announced.
The Prime Minister’s spokesman told reporters on Tuesday afternoon: “The important message whilst the alerts are in place is that we urge everybody to follow the Environment Agency’s advice and check their flood risk and sign up to alerts.”
Mr Claydon also said: “It’s not going to be a short burst of bad weather like you may think of in terms of storms in the past where it quickly blows through overnight.
“It’s really persistent heavy rain, the rain really is going to be persistent, just continuing all the way through today and tomorrow and into Thursday, it’s really just the prolonged accumulation of rainfall rather than a short come and gone weather event,” he said.
On Tuesday evening, the Environment Agency had issued 19 flood warnings and 137 less serious flood alerts across England.
Calderdale Council in West Yorkshire said flood sirens in the village of Walsden in the west of the county had been activated, telling residents to turn off their utilities.
The council’s chief executive Robin Tuddenham later said no further activation of sirens was expected overnight as river levels were high but stable.
A major incident was also declared in Greater Manchester on Tuesday.
Assistant Chief Constable Nick Bailey, chairman of the GM Strategic Co-ordination Group for Storm Christoph, said: “Whilst we appreciate that everyone has been told to stay home due to the coronavirus pandemic, we want to make it clear that should members of the public need to evacuate to protect themselves due to flooding then that is the priority and you should follow your local authority’s advice regarding evacuation.”
Floodwaters have already risen in parts of the country, with a motorist pictured stranded in Leicester, and workmen in York prepared flood defences on Tuesday morning near the city’s River Ouse.
A major incident had already been declared in South Yorkshire in anticipation of flooding that could arrive in the coming days.
Mayor of Doncaster Ros Jones tweeted on Monday evening: “Key risk areas have been inspected over the past 36 hours, sand-bags have been handed out in flood-risk areas & will continue over the next 24 hours.”
On Tuesday, North Yorkshire Police and North Yorkshire Fire and Rescue Service warned drivers not to take risks ahead of the expected weather.
A spokesperson said: “Just 60cm of standing water and 30cm of flowing water can be enough to float/move your vehicle. So please don’t take the risk!”
North Yorkshire County Council said more than 15,000 sandbags are at the ready around the county.
The Local Government Association (LGA) has advised people to check with councils to keep up to date with advice as the storm moves through.
The LGA said in a statement: “They will share flood warnings and other relevant information so people should make sure they regularly check their council’s website and social media and follow their advice.”