‘Thundersnow’ alert as mercury hits -7C
SCOTS are being warned to prepare for ‘thundersnow’ this weekend as a polar air mass sweeps the country.
Forecasters are predicting more snowfall and storms with the potential for thunder and lightning, mainly in western areas.
A yellow ‘be aware’ warning for wintry showers was issued by the Met Office yesterday afternoon and will be in place until 10am today.
The warning states: ‘A cold northwesterly airstream will continue to bring heavy showers or rain, sleet, snow and hail. Clear spells in between will allow temperatures to fall close to or below freezing, hence the likelihood of some ice.’
Thundersnow appears when thunderstorms form in wintry conditions, often resulting in heavy downpours of snow.
It is triggered by cold air passing over warmer seas, picking up warmer, moist air which cools rapidly as it rises, condensing into water drops which freeze as ice crystals.
Usually, these would melt and fall as rain, but in winter the ice can freeze, falling as snow.
Met Office spokesman Oliver Claydon said: ‘Thundersnow is essentially snow and thunder, with potential lightning. It is usually described as hail, thunder and heavier rain, or sleet.’
He added: ‘Showers could fall as snow above 150m (500ft) of elevation, and there will be tricky driving conditions. We warn people to be extremely careful when travelling.’
Areas likely to experience extreme weather conditions over the next few days include North Lanarkshire, Glasgow, parts of the Highlands and the Borders.
Dumfriesshire, Renfrewshire and Ayrshire are also braced for the latest wintry weather.
Across the west of Scotland heavy showers could see up to an inch of snow on lower ground. Land above 1,300ft (400m) could see more than two inches fall.
Yesterday parts of the country woke up to snow and ice. In Braemar, Aberdeenshire, temperatures fell to -7.2c, making it the coldest night of autumn so far.
Traffic Scotland has urged motorists to allow for longer journeys. A spokesman said: ‘Wintry showers, continuing during Friday and overnight, will lead to the possibility of ice forming as temperatures fall.
‘This will occur primarily on untreated surfaces.’
Elsewhere, gales and torrential rain storms are set to hit much of England and Wales, with wind speeds of up to 65mph.
Recent snowfalls have prompted a flurry of bets on a White Christmas, with Ladbrokes slashing their odds for snow in Britain on December 25 to 2/1.