The mercury plunged to -21.9 degrees Celsius in Pyeongchang on Wednesday, brought down to as low as -36.4 degrees by winds blowing at a speed of 11.4 m/s. If the area is hit by such an extreme cold during the Winter Olympics, it could seriously affect the event. Weather is one of the biggest factors that will determine the success of the games.
The organizing committee is preparing for the worst with five scenarios using data compiled over the last 30 years.
The biggest impediment would be heavy snowfall. Some 174.1 cm of snow fell in Pyeongchang and Jeongseon during from Feb. 9 to 25, 2014.
It will be impossible to use snowplows or other snow-clearing equipment on the alpine slopes of Jeongseon, and people would have to be mobilized to shovel snow. Taking visitors from railway stations or parking lots to the venues would also take a lot of effort. The committee will put personnel and snow-clearing equipment on 24/7 standby during the Olympics.
Sudden gales are the worst enemy of ski jumping. Ski jumping will be suspended when winds blow at a speed of more than 3 m/s. The organizers built a windbreak fence around the venue in November 2016 that can reduce wind speed effectively from 18 m/s to 2.4 m/s.
Biting cold wave could also affect the opening and closing ceremonies seriously. The best temperature condition for outdoor events is between -5 degrees and -10 degrees.
Most outdoor events, including the biathlon races, will be suspended if the mercury drops below -20 degrees, no matter how clear the sky is.
The committee has built warming shelters in and near the venues.
Fog formed by low-hanging snow clouds is another problem. At least two gates marked by wide flags tied to pairs of poles must be in clear sight for an alpine skiing event. It is impossible to conduct the biathlon unless athletes can see the shooting target 50 m away. Nobody knows what will happen since fog formed in Pyeongchang for an average of 3.8 days during the previous Winter Olympic games in other host countries.
Another possible headache will be rain. If the weather warms and rain falls, high temperatures and humidity could cause damage to indoor ice rinks as well as outdoor snow events.
The committee has a staff of 73 weather experts. They will measure temperatures, sky, humidity, and wind speeds, using four automated weather sensors and 25 integrated sensors inside sports arenas. In the event of bad weather, the committee will discuss rescheduling with the International Olympic Committee and the international organization of each sports event.
But it will be still impossible to prepare for all eventualities.
Lim Jang-ho of the committee said, "It's possible to forecast weather for the next three to four days in the flatland. But it's difficult to predict it in mountainous areas like Pyeongchang. God help us manage the important Olympics smoothly and safely!"