Many areas across Japan are expected to be affected by the coldest air mass of the season from Tuesday.

Weather officials warn that temperatures may drop to the lowest in a decade across the country, affecting transportation and freezing water pipes.

They are advising people to prepare for heavy snow and low temperatures and refrain from going out in the worst of the weather.

The Meteorological Agency says the effects of a winter-type weather pattern have already been bringing snow, mainly to areas along the Sea of Japan coast from northern to western Japan.

It says in the 3 hours to 11 a.m. on Tuesday, Daisen in Tottori Prefecture had 14 centimeters of snow, while Gojome Town in Akita Prefecture had 9 centimeters.

The weather pattern is expected to become stronger and bring the most powerful cold air mass to the skies above northern to western Japan by Tuesday night.

This will cause snow and winds to intensify and bring heavy snow and blizzards, mainly to areas along the Sea of Japan coast. Snow may accumulate rapidly.

The snow may also intensify and accumulate in Tokyo, and some pockets may have about 2 centimeters by noon on Wednesday.

Snowfall in the 24 hours to noon on Thursday is expected to reach 50 to 70 centimeters in Tohoku, 40 to 60 centimeters in Niigata Prefecture, 30 to 50 centimeters in Hokkaido, Hokuriku and Kinki, 20 to 40 centimeters in Kantokoshin and Chugoku, and 10 to 20 centimeters in Tokai and northern Kyushu.

The overnight lows on Wednesday are expected to be minus 12 degrees Celsius in Sapporo City and minus 7 degrees in Nagano City. Lows of minus two degrees are expected in central Tokyo and Osaka City.

Weather officials are warning people to be careful of heavy snow, blizzards, frozen roads and other effects on transportation, violent winds and high waves. They are also calling on people to be alert to frozen water pipes and power outages due to the snow.