Britons endured a bitterly cold night as temperatures plunged towards -7C during a sharp cold snap.
The mercury fell to its lowest level of the year as the UK entered what the Met Office described as a colder spell of weather.
Forecasters warned of a particularly cold Friday night, followed by a widespread, frost-covered start to Saturday across England and Wales.
The lowest temperature recorded was -6.6C at Sennybridge in Wales, while several other areas also experienced severe overnight chills.
Shap, near Penrith in Cumbria, and Eskdalemuir in Dumfries and Galloway, both dropped to a freezing -6.5C.
Saturday will bring more unsettled conditions, with brisk winds, heavy rain and showers moving eastwards from the west across much of the country.
Daytime temperatures are forecast to range from 5C in Norwich and Manchester to 11C in Plymouth.
Central and eastern England should remain largely dry, with clear spells and a particularly heavy frost expected.
A deer leaps across frost-covered grass in Richmond Park on Saturday morning
A cyclist wearing thermal clothing and a bandana rides through a park after the overnight temperature drop
A runner takes on the frosty conditions at Wimbledon Common on Saturday morning
A walker makes their way through Richmond Park in south-west London on a notably frosty Friday morning
People arrive at Avon Beach in Dorset ahead of a chilly sea swim yesterday
A woman runs through a park in Wimbledon, south-west London, on November 14
The season’s first yellow cold-health alerts were issued for the North West and West Midlands this week
Snow could develop in north-west Scotland over the weekend, although frost has been less widespread there because of cloudier skies.
Met Office chief forecaster Chris Bulmer said: ‘The UK forecast has moved into a colder phase, with daytime temperatures likely to remain in single figures across most areas.
‘Temperatures will fall again on Friday night, reaching -4C and potentially as low as -6C in some places, bringing another significant ground frost for many.’
Friday marked the first widespread autumn frost, following what the Met Office called the coldest night of the season so far.
The freezing conditions are expected to ease somewhat by Sunday, when temperatures should remain above zero during the morning.
There will be some sunshine in eastern areas early in the day, spreading to the far north and west later on.
Elsewhere, skies will be mostly cloudy and winds will be brisk, with spells of rain—some of it heavy—and the possibility of snow over northern hills.
Met Office deputy chief forecaster Steven Keates said: ‘The outlook is unsettled, with periods of rain, sleet and some snow over higher ground.
A man takes his dog for a brisk morning walk through a London park over the weekend
A paddle boarder faces the freezing water and weather in Dorset yesterday morning
Mist hangs above a river flowing through frost-covered Richmond Park on November 13
Frost coats car windscreens on a residential Wimbledon street after temperatures plunged overnight
‘Low pressure will bring rain or showers to many parts of the UK on Sunday.
‘Rain is expected to be most persistent across northern Scotland, where the chance of snow will increase later in the day.
‘Most of the snow will fall over higher ground, where accumulations are possible, although some may reach lower levels. Ice could also become a hazard.’
The UK Health Security Agency issued the first yellow cold-health alerts of the season for the West Midlands and North West this week.
The alerts began at 9am on Thursday and will remain in force until midday on Saturday.
The warnings indicate that cold weather is likely to cause minor disruption to health and social care services, including increased demand for medical help and a heightened risk to vulnerable people, the agency said.
Dr Anya Gopfert, a UKHSA consultant in public health, said: ‘This is the first cold-health alert of the winter, but further alerts can be expected as the season progresses.
‘Cold conditions can seriously affect some people’s health, particularly those aged 65 and over and people living with existing health conditions. It is important to check on vulnerable friends, relatives and neighbours.’
Dr Gopfert also advised people to keep their homes heated and wear warm clothing to reduce the risks posed by the cold.
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