Extreme snowfall hit mainly Fujiwara and Minakami regions and islands Honshu and Hokkaido. About severe blizzard Mkweather has informed already during last week /https://mkweather.com/2020/12/18/extreme-snowstorm-hit-japan-2-meter-snowdrifts-buried-1000-people-on-highway-for-40-hours//, when 2 meter snowdrifts buried 1000 people on highway for 40 hours.
Such was written in the mentioned article: "People must alive in snow and ice long 40 hours without water and food and slept in their cars according to many sources."
The worst conditions hit lower situated parts of Japan around a week before a Christmas 2020, but in higher elevated regions, snowfall was continuing longer and after blizzard, heavy frosts hit Japan around the weekend.
In Fujisan (3772 MASL), temperatures have dropped into -24,6°C on Saturday, 19. December and in Kutchan, 176 MASL, -19,2°C was measured. Severe frosts hit only few days before a Korean Peninsula, too /https://mkweather.com/2020/12/18/extreme-frosts-in-korea-north-korea-275c-south-korea-235c-and-30-degree-frosts-in-outlook//.
Shortly after the Christmas, next severe blizzard and coldwave hit Eastern Asia, including Siberia, eastern China, Mongolia, Korean Peninsula and Japan.
In Verkhoyansk region, mimimum temperatures on 23. December already have dropped up to -54°C and maximum temepratures are moving around -51°C these days.
At Christmas and after Christmas, possible frosts below -60°C, in early January maybe up to -65°C are possible in Siberia thanks to extreme atmospheric blocking, NAO- phase and SSW (Sudden Stratospheric Warming) /https://mkweather.com/2020/12/22/january-2021-forecast-for-the-world-from-ecmwf/; https://mkweather.com/2020/12/17/extreme-winter-hit-yakutsk-siberia-58c//.
Infographics: source - Jurnal de Vreme, FB