Storm Ellen has become the first named storm during the summer holidays, as the country braces for 75mph winds and flooding.
The storm is set to be the worst for six months since Dennis battered the country and left many homes and businesses destroyed.
The fifth named storm of the 2019-2020 season is due to strike Ireland on Wednesday evening before moving north towards Scotland.
The deepening low pressure system has led the Met Office to issue a series of yellow weather warnings until Friday, with travel disruption expected.
One warning predicted that strong winds could affect an area stretching from the west coast of Scotland, across the Irish Sea, western Wales and down to Plymouth and Cornwall from 8pm Wednesday through to 4am Friday.
Campers and staycationers have been warned of the brutal winds and flooding due to hit the south-west coast on Wednesday evening.
Waves of 26ft were due off south-west coasts, with waves up to 15ft on beaches in the south west, and strong winds are predicted to hit the country over four days until Sunday.
There are flood alerts in place from the Environment Agency in Devon and Cornwall, which are packed with holidaymakers this summer.
Forecasters predict gusts could bring delays to road, rail, air and ferry transport links and disrupt power supplies.
They warned that coastal routes and communities, as well as sea fronts, could be hit by spray and large waves while tree damage could leave debris in roads.
Ellen is the first storm named in school summer holidays by the Met Office or Ireland’s Met Eireann since they began naming Atlantic storms in 2015.
Marco Petagna, a Met Office forecaster, said: “Storm Ellen’s very unseasonable conditions come with the tourist season in full flow and trees in full leaf. The low pressure is deepening, with warnings issued for winds of 70mph plus in some exposed areas.
“It will be wet and windy on Thursday and Friday, with further strong winds and squally rain bands. And big waves will develop on some west coasts, combining with high tides.”
The Environment Agency said: “Local flooding is possible from surface water and rivers on Thursday evening in the South West, and from large waves and high tides on Thursday and Friday in the South West, Wales and the North East. Land, roads and some properties may flood and there may be travel disruption.”
Isles of Scilly Travel said it had cancelled sailings for Wednesday, Thursday and Friday “due to the forecast storm force 10 winds and the six-metre swell”.
A Twitter account for the CoastSafe campaign, a partnership involving HM Coastguard and emergency services in Devon and Cornwall, warned that a combination of strong winds and spring tides “will make our coastlines hazardous for the next few days”. It added: “Swell will increase in size… Tidal surges will force water on to beaches at a faster rate… Beware of debris & overtopping around harbours/promenades.”
It also warned potential weather watchers: “No photo is worth a life.”
Nicola Maxey, a Met Office spokesman, said: “This time of year we’ve still got lots of people who are out enjoying outdoor activities, they’re walking on the coast, they’re camping.
“So certainly take care, be aware of the warnings and it may be worth thinking about, if you’ve got garden furniture or trampolines, children’s toys in the garden, bringing them inside or making sure they’re secure.”
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