What is 'freezing rain' and why is it so dangerous?
Parts of England and Wales face 'treacherous conditions' this weekend caused by freezing rain.
Large parts of the UK are facing heavy snow and freezing rain on Sunday, with the Met Office warnings of "treacherous conditions" in some places for travellers.
An amber warning for snow and rare freezing rain covering most of Wales and central England, including the Midlands and the north-west cities of Liverpool and Manchester, in place until midday on Sunday, said the forecaster, which has issued several other warnings for rain, snow and ice across the UK this weekend.
Met Office chief forecaster Jason Kelly said some "significant accumulations" of snow are possible in parts of Wales, the Midlands and northern England, and the additional factor of strengthening winds could lead to drifting of lying snow.
He continued: "There is a risk of freezing rain across parts of the Midlands and northern England, but especially Wales, adding to the risk of ice and leading to some treacherous conditions in places.
"As the super-cooled rain droplets hit the surface they instantly freeze, covering everything in a layer of ice, making it extremely dangerous."
It comes after the UKHSA issued an amber "cold health alert" for all regions of England until at least midday on Wednesday, warning of a greater risk of death, particularly among those aged 65 and over or with health conditions.
What is freezing rain?
Freezing rain forms when droplets hit surfaces below freezing - 0 C - and turn into ice on impact.
Often, rain falls from a cloud in snow form before passing through warmer air and turning into rain droplets. But when those droplets, on rare occasions, fall through cold air again, they can be "supercooled".
This means they are "still falling in liquid form," the Met Office says, "even though their temperature has fallen below zero.
"When this 'supercooled' droplet hits the ground (which is below zero too) it spreads out a little on landing, and then instantly freezes, encasing the surface in a layer of clear ice. This is why it is called freezing rain."
It can result in pretty pictures such as this...
... but it can actually be very serious. As per the Met Office, "the weight of the ice can sometimes be heavy enough to bring down trees and power lines, and the glaze of ice on the ground effectively turns roads and pathways into an ice rink.
"The freezing rain can also prove extremely hazardous for aircraft."
Tips and advice to stay safe
Amid the freezing rain warnings, motorists in particular are being to take care, even in conditions that may appear "normal".
Darren Clark, severe weather resilience manager at National Highways, said: "If you are travelling this weekend, keep your distance and reduce your speed. Gritters will be out treating our roads around the clock when ice or snow is forecast, but it is still important to drive to the conditions.
"Even in conditions that seem normal and where the snow is not settling you could always experience slippery conditions."
