TOKYO, Jan. 4 (Xinhua) -- Japan's weather agency said Saturday that heavy snow had hit the mountainous areas on the Sea of Japan side of northern to western Japan, urging people returning from their new year holidays to brace for traffic disruptions.

In the six hours up to 6 a.m. local time on Saturday, 17 centimeters of snow had piled up in Itoigawa City in Niigata Prefecture and 14 centimeters in Chippubestu Town in Hokkaido, according to the Japan Meteorological Agency (JMA).

As of 6 a.m. local time, 392 centimeters had piled up in Sukayu in the Hakkoda mountain range in Aomori Prefecture, double the average amount for this time of year, while Goshogawara City in the same prefecture saw 107 centimeters, more than triple the average, said the JMA.

In the 24 hours through Sunday morning, 40 centimeters of snow is expected in Hokkaido and 30 centimeters in the Tohoku region, it added. ■