‘Intense’ polar vortex could bring ice storm to New Territories: chill running through Hong Kong expected to last a week
History of snow falls and frost in Hong Kong show it’s not impossible it could happen again
A polar vortex is expected to hit the New Territories but could spare urban areas from frost, ice and sleet over the weekend.
The Hong Kong Observatory predicts chilling conditions over the coming weekend which some internet commentators have said could bring snow.
While snow may seem unlikely, frost and ice is expected, said Christy Leung, HKO Scientific Officer.
“I think there could be chances of frost or ice in the NT or on high ground,” she said. “We expect it will be a few degrees lower than the urban areas.”
But the coming ice-storm is not so unbelievable in the sub-tropical city. Peaks in Hong Kong like Tai Mo Shan have been put in the deep freeze during polar vortex conditions before – frost was even seen in Fanling in March 2010.
The lowest temperature the HKO has observed is water’s freezing point, zero degrees, in 1893, but snow has hit at ground level another four times at least, in February and December 1967, in January 1971 and December 1975.
The Observatory’s blog added that since air temperatures are measured two metres above the ground then it may have been colder below, making frost a more common and understandable occurrence.
Ms Leung said the coming icy blast was linked to the polar vortex which sends cold Arctic air to Hong Kong.
“As the polar vortex will build up in northern China this week, that’s the reason why we will experience a cold surge,” she said.
“It’s not that abnormal for these kind of vortexes to build up, and for cold weather to affect Hong Kong.
“Of course the strength of this cold surge that will build up this weekend will be quite intense,” she said.
The polar vortex, a normal weather pattern that normally circles the Arctic confined by the jetstream, may have been distorted as the ice cap melted, the HKO reported last year on its blog.
The distortion has sent the chilling wind much further south than normal with the aid of the jetstream, which has also modified as the globe warms.
Ms Leung stepped back from suggesting the coming cold snap was a product of global warming and climate change, as there is no consensus in the scientific community on that topic.
— Observatory HKO (@ObservatoryHK) January 18, 2016
“Currently for our current projection we expect global warming effects, like hot days,” she said. “But for individual events like extreme cold it is difficult to predict.”
But she didn’t rule out snow on the top of tall buildings in central Hong Kong and Kowloon, adding that likelihood drops in urban areas as the temperature is usually a few degrees warmer.