The red weather warning – the highest alert, which means a lot of impact – has been issued due to a combination of strong waves, strong winds and hurricane waves, which is considered an unusual event for the UK.
Snow and severe winters are expected in Scotland.
The Met Office said there was a “risk to life as a result of flying debris” and “damage to buildings and homes as roofs fly and power lines fall.”
The warning covers the coast of Wales as well as the coast of Devon, Cornwall and Somerset and will be in effect from 7am to 12pm on Friday.
Amber Warnings, the second highest alert level for the wind, is issued across England from 5am to 9pm on Friday, while yellow weather warnings, down to the next level, for wind and snow over a large part of Scotland. Are applicable to – where blizzards are predicted – and throughout Northern Ireland.
With the storm approaching, London North East Railway has urged Friday ticket customers to travel on Thursday or Saturday instead or get a refund due to the expected disruption and loss.
Hurricane Younes: When and where will Hurricane Younes hit, where will it snow in Scotland?
The East Midlands Railway, the Southeast and the West Coast have also appealed to people not to travel, with trains being canceled, delayed and disrupted.
A Network Rail spokesman said the disruption was “inevitable” and that Welsh services would be suspended for the day.
Passengers have been advised that the weekend is likely to be disrupted as more than 1,000 miles of track in Wales has been checked and cleared of debris and fallen trees.
At Cornwall, residents are being urged to exercise caution and travel only if absolutely necessary, while in North Somerset, people are being encouraged to stay home.
The Prince of Wales has canceled a planned visit to Newport and Swansea as a result of the forecast.
A Clarence House spokesman said: “Following official guidance, the Prince of Wales’ visit to Newport and Swansea on Friday 18 February will not proceed due to the dangers posed by Hurricane Younis.
The Environment Agency has issued severe flood warnings for parts of Severn and Wystores in southwest England and South Wales ahead of Hurricane Younis, meaning strong winds and high waves are “life threatening”. Wave
Severe flooding is expected Friday morning on homes and main roads, as well as Hurricane Elmoor to Rodley and Hampstead, Gloucester, along Browardock, Apney, Freimlood, Frampton, Newham, Pride, Saul and Westbury’s Severn Story. Near Munster Worth and Stone Bench.
Similar warnings are available at Wye Estuary in Brockweir and Elmdale in Chepstow.
People in these areas should take “immediate action” and implement emergency flood plans.
The meteorological agency said the water level would remain high for a long time due to strong winds and high tides.