A youth worker from Northern Ireland who lives in Scotland has told how he threw a cup of boiling water into mid-air - and saw it transform into ice crystals.
atthew Hamilton (22), who recently moved to Aberdeen with his wife Rebecca, said he had been "absolutely freezing" for the past week in the cold snap - which has seen temperatures plummet to their lowest level in years.
He decided to try out the stunt, in which people throw water in the air and it freezes instantly if it is cold enough, on Wednesday, when the mercury was as low as minus 10C.
The phenomenon is caused by small water droplets becoming so hot that they start to vaporise.
Because cold air is unable to hold as much water vapour as warmer air, the water condenses.
The cold temperatures then freeze the droplets of water, creating ice crystals.
Mr Hamilton said: "We were sitting in the living room and we had the idea to do a video like they do in Russia, where you throw a cup of hot water into the air and it freezes.
"I thought that it must be getting that cold here, so I went out with a mug of hot water and, as soon as it hit the air, it froze."
Mr Hamilton said he would definitely remember to put on extra layers next year after his initial experience in Scotland.
"We have the heating blasting and the fire lit 24/7 these days. Newtownwards is like the tropics compared to this," he added.
Mr Hamilton staged the stunt after temperatures dropped to minus 23.0C (minus 9.4F) in Braemar, Aberdeenshire, the coldest temperature recorded in the UK since 1995, according to the Met Office.
Forecasters said the last time a temperature below minus 20C had been recorded in the UK was on December 23, 2010.
Nicola Andrews, from Castlerock and now living in Aberdeenshire, also told of her experience.
"Over the past week we have had just over half a metre of snow and last night the temperature dropped to minus 20 degrees," she said.
Locally, a yellow weather warning is in place for snow in Northern Ireland on Saturday.
Oli Claydon, from the Met Office, said cloud and wind were expected over the next couple of days, with Friday forecast to be dry before conditions change again on Saturday.
"There's a yellow snow and ice warning starting at midnight that goes through to Saturday night as well," he added.
"The total snowfall will be one to four centimetres quite widely, with five to 10 or even up to 15 on higher ground. We've got a front moving from west to east, and as it bumps into the cold air that's in place, it's going to start mostly rain but also snowfall as it moves across Northern Ireland and further south.
"Some clarity will come through after that, and it's that system on Sunday that will bump the cold air out of place across the UK.
"Behind that, we'll see much milder temperatures, with milder air in place and more risk of rain that day. On Monday, temperatures are milder."
A temperature of three degrees is expected on Saturday, followed by 10 and 11 on Sunday and Monday respectively.
Mr Claydon explained: "There has been a noticeably cold period across the UK. It was mostly in eastern (areas), but the snow itself is quite fleeting.
"It's not completely unusual. It's probably similar to what we saw in January and February 2019 and a similar end to the Beast from the East in 2018, but there will be a snowy period over the next couple of days."