The Environment Agency has warned drivers their cars can be swept away in just 30cm (12in) of water as more than 60 flood warnings were issued in England after heavy rain overnight, with further downpours to come.
Flooding disrupted rail services in England and Wales on Thursday morning and caused the M5 motorway to be closed in both directions in Gloucestershire.
The Met Office has a yellow warning in force for heavy rain covering the southern half of England and Wales, with the Midlands worst affected. At 8am on Friday, the Environment Agency (EA) issued 66 flood warnings in England and a further 121 flood alerts.
About 385 properties were flooded in Hertfordshire, Bedfordshire, Northamptonshire, Kent and the home counties, the EA said.
Caroline Douglass, the EA’s executive director for flood and coastal erosion, advised motorists not to drive through submerged patches of road.
Speaking on BBC Radio 4’s Today programme, she said: “Don’t take a risk and drive through flood water, because it only takes 30cm to float your car … It’s probably about half the height of your tyres.”
Douglass said drivers tended to underestimate the risk: “They think a car is very heavy object and hard to move. But 30cm is not much water. And many of these waterways are much more fast-flowing than people will realise.
“It really doesn’t take much to make a vehicle float, and so in that case, it will be swept away. We really don’t want to see the sorts of tragic circumstances, we’ve seen this year and in previous years.”
She urged people to avoid walking near rivers or watercourses over the weekend, and to keep their pets and children safe.
Douglass said the agency was particularly concerned about flooding in the Midlands. “Over the last week or so, we’ve seen heavy thunderstorms and downpours, which have saturated particular areas. And then, as we move over the weekend and into next week, we’ll see more traditional winter rainfall that is more widespread and, unfortunately, that’s then going to be landing on already saturated ground. The Midlands are [likely] to be the most affected.”
According to the Met Office warning, wet conditions could lead to difficult driving conditions and road closures, homes and businesses are likely to be flooded and there some communities could be cut off by flooding.
“There will continue to be localised flooding. A lot of these areas have been hit by rain in the past few weeks which means the ground is already saturated,” the meteorologist Greg Dewhurst told PA Media.
He said that although conditions were expected to “ease up” throughout the day, “rivers often take time to respond so we’re expecting disruption to continue in central and southern parts throughout the morning”.
”Those planning to travel on Friday should factor this into their journey times,” he added.
Avon fire and rescue service said it was working with National Highways: South-West to rescue people stranded on the M5 in Gloucestershire after heavy rainfall flooded the motorway.
National Highways said the M5 was closed northbound between J16 and J14 and the southbound carriageway was shut between J14 and J15 as emergency services worked to clear the flooding.
Councils and emergency services in Northamptonshire and Hertfordshire confirmed a number of road closures and reassured residents they were working to keep people safe overnight.
Tewkesbury borough council, in Gloucestershire, has been handing out sandbags to residents to help protect their homes against flooding.
National Rail warned passengers that the wet weather could affect train journeys in England and Wales on Friday. There would be no trains to and from Aberystwyth until 1pm, and disruption expected between Bicester North and Banbury in Oxfordshire until 3pm, while the line between Ledbury and Hereford was also blocked on Friday morning.
Services between Shrewsbury in Shropshire and Wolverhampton in the West Midlands were cancelled due to severe flooding at Wellington station, as well as a tree falling on the line earlier, and trains between Peterborough and London King’s Cross were delayed because of flooding.
The Marston Vale line in Bedfordshire, which operates services between Bedford and Bletchley, has also been suspended until Monday because of standing water on the track.