Storm Éowyn was named by the Met Office today as winds of 80mph will cause chaos across Britain from Friday, along with heavy rain and snow arriving on Thursday.
The fifth named storm of the 2024/25 season comes after Darragh on December 6, Conall on November 27, Bert on November 22 and Ashley on October 20.
A yellow wind warning applies in Scotland and northern England from midnight on Friday until midday on Saturday.
The Met Office today updated Friday's warning to include most of Britain, excluding Ireland, the north-west areas of Northern Ireland, London and the south-east.
Unsettled conditions will begin to arrive in Britain on Thursday, with stronger winds and heavy rainfall expected in western parts of the country overnight, the Met Office said.
It follows the 'benign' gray, cloudy weather and rain showers that much of the country saw earlier this week.
Storm Éowyn's 80mph winds will lash flagged areas of Britain on Friday and Saturday as gusts are pushed across the country by a powerful Atlantic jet stream.
The Met Office said the 'very strong' south-easterly to south-westerly winds could cause damage to buildings, disruption to public transport, road or bridge closures and power outages – while 'injuries and danger to life could result from flying debris'.
The yellow wind warning was in force from midnight on Friday until midday on Saturday and previously covered areas in the north, but was updated this afternoon to include most of Britain
A Met Office weather forecast map shows the winds of Storm Éowyn blowing across Britain on Friday
The icy Arctic air flowing southward across North America and the much milder air further south are preparing to collide, boosting the Jet Stream
And it urged those in the warning area: 'Prepare to protect your property and people from harm. Check for loose items outside your home and plan how to secure them. Items include; containers, garden furniture, trampolines, tents, sheds and fences.'
Inland, wind speeds can reach 80 to 100 km/h and around the western coastal areas, wind gusts can reach between 110 and 130 km/h.
In recent days the Jet Stream over Britain has been weak and spreading causing high pressure to linger nearby, preventing strong weather events.
This will change on Thursday, however, as a stark temperature contrast between the collision of icy Arctic air flowing southward across North America and the much milder tropical air further south will 'supercharge' the Jet Stream.
The Jet Stream will develop over the North Atlantic Ocean, with core wind speeds forecast to exceed 260mph, as the Met Office predicts 'perhaps the strongest winds of the winter so far' on Friday.
The powerful injection of energy high into the atmosphere will see an area of low pressure deepen rapidly as it heads towards Britain, bringing storms and the threat of disruption on Friday and Saturday.
Heavy rain is also expected to hit the north-west of the country, with temperatures remaining cold enough to see snow fall on hills in Scotland, northern England and Northern Ireland.
Storm Éowyn will bring an extended period of more turbulent conditions, with computer models suggesting further deep areas of low pressure could pass close to Britain next week.
A person crosses the street as people travel in foggy weather in the morning in Walthamstow, East London on January 21
The Met Office's wind forecast maps for Friday and Saturday previously showed the yellow warning in force across northern and western Scotland and Northern Ireland, but this has since been updated to include most of Britain.
The frigid Arctic air moving south across North America on Monday is preparing to collide with tropical air further south of the world
The contrast between the cold Arctic air and the warmer tropical air further south will 'power' the Jet Stream
On Wednesday, the Jet Stream will reach speeds of up to 400 km/h over the Atlantic Ocean as it heads towards Britain
The Jet Stream will reach Britain on Friday, bringing in Storm Éowyn, with wet and windy weather expected for all
Gray clouds will cover much of Britain today with more rain expected in some northern parts of England, Wales and northern Scotland.
Many commuters across the country were confronted with thick blankets of low-hanging fog on their way to work this morning.
The showers will move across the country to southern England on Wednesday.
The big change in weather on Thursday will create a front that will bring heavy rain showers as it travels eastward throughout the day.
The highest accumulations of heavy rain are expected in North Wales and North West England, where 20-30mm could fall over the hills with some chance of snow over the Scottish mountains.
The strongest storms are forecast to hit Northern Ireland and western Scotland on Friday, where speeds could exceed 80mph along coastlines and on high ground.
Because the weather warning was issued five days in advance, it is likely to be updated with further information in the coming days as more accurate data becomes available.
