TOKYO (Kyodo) -- Heavy snowfall continued Wednesday along the Sea of Japan coast as the season's strongest cold front disrupted rail services in central Japan and air traffic, with the weather agency warning of more snow toward the weekend.

All Nippon Airways and Japan Airlines canceled some of their flights due to the bad weather, including those between Tokyo and Tottori Prefecture in western Japan and between Shimane Prefecture, also in western Japan, and the Oki Islands in the Sea of Japan.

In central Japan, some local train services through Ishikawa, Gifu and nearby prefectures were canceled, including an express train on JR West's Nanao Line that experienced a brake malfunction due to frost.

In Shirakawa, Gifu Prefecture, the amount of snowfall reached 129 centimeters in the 48 hours through 5 p.m., a record high, the Japan Meteorological Agency said. Snow accumulated up to 50 cm in Toyama in the 12-hour period through 5 p.m., 48 cm in Shirakawa and 45 cm in Jyoetsu, Niigata Prefecture.

Kagoshima in southwestern Japan also saw 2 cm of snow over six hours.

Casualties have been reported amid the severe weather, including a man in his 50s who hit his head after falling from a forklift while clearing snow in Tonami, Toyama Prefecture.

In Yamaguchi Prefecture, western Japan, a 62-year-old woman died after an 18-meter tree fell on her while she was guiding vehicles for the removal of another tree that had touched a power cable. Police said the tree may have fallen due to snow-loosened ground.

The weather agency warns of extremely unstable atmospheric conditions as cold air of minus 39 C or lower moves into an area 5,000 meters above eastern to northern Japan, potentially forming cumulonimbus clouds in some parts of the country.

The weather agency warns that heavy snowfall is expected not only along the Sea of Japan coast but also on the Pacific side, where snow is rare.