Weather officials are warning of more snow in Hokuriku and other areas along the Sea of Japan.
The Meteorological Agency says a strong winter pressure pattern and a mass of very cold air have dumped a large amount of snow, mainly in the Hokuriku region and Niigata Prefecture.
In the city of Itoigawa in Niigata Prefecture, 26 centimeters of snow fell between 1:00 a.m. and 4:00 a.m. The agency issued information on a significant amount of snow as it may cause massive traffic disruptions.
It says the pressure pattern is likely to persist through Monday morning. Snowfall is expected mainly along the Sea of Japan from the north to the west.
Intermittent and heavy snow is expected in the Hokuriku region and Niigata Prefecture. It is expected to continue until Tuesday morning.
The depth of snow has already reached two to nine times the level for the average year in some coastal areas from Tohoku to Chugoku.
Weather officials are urging people to be on the alert for possible disruptions of traffic due to snow accumulation and icy roads. They also warn that avalanches and snow on power lines could trigger blackouts.