Japanese weather officials warn that the coldest air mass of this winter is expected to bring heavy snow to the Sea of Japan coast and some areas on the Pacific side of the country from Tuesday.
They are urging people to prepare for the heavy snow and cold temperatures as soon as possible.
The Meteorological Agency says snow will start falling before dawn on Monday in the Chugoku, Shikoku and Tokai regions. Snow will also accumulate in low-lying areas.
A cold air mass will flow into western and eastern Japan between Tuesday and Wednesday. It will be about 15 degrees colder than those that are usually observed at this time of the year.
The cold air mass will bring heavy snow and strong winds to the Japan Sea coast from northern to western Japan. If the snow clouds linger, they could dump a large amount of snow in a short time.
Officials say low-lying areas on the Pacific side of Kyushu and Shikoku may also have heavy snow.
In the 24 hours through Tuesday evening, the Tohoku region is expected to have 40 to 60 centimeters of snow, and Hokuriku, Niigata, Tokai, Kinki, and Chugoku could have 20 to 40 centimeters. Kanto-Koshin, Shikoku, and northern Kyushu may have 10 to 20 centimeters.
In the 24 hours through Wednesday evening, 70 to 100 centimeters of snow is expected in Niigata, 60 to 80 centimeters in Tohoku and Hokuriku, and 50 to 70 centimeters in Kanto-Koshin, Tokai, Kinki, and Chugoku. Shikoku and northern Kyushu may have 20 to 40 centimeters, and southern Kyushu, 10 to 20 centimeters.
Weather officials say winds will intensify across the country, and rough waves are expected off the coasts of eastern and western Japan as well as Okinawa and Amami.
On Wednesday morning, temperatures will plunge to 11 degrees below freezing in Sapporo, minus 8 in Nagano, minus 6 in Sendai and minus 3 degrees in Tokyo.
The Meteorological Agency warns that snowstorms could disrupt transport services and cause power outages. Water pipes could also freeze. It says residents of areas where heavy snow is expected should avoid going out if possible.