The transport ministry announced Tuesday that highways in the Tokyo metropolitan area will be closed as a preventive measure ahead of a forecast for heavy snow later in the day.

The closures are set to begin from 3:30 p.m. on the Central Circular Route of the Shuto Expressway and 4 p.m. on major routes including the Tomei Expressway, Shin-Tomei Expressway and Joshinetsu Expressway, along with several smaller national highways.

Additional closures on the Tohoku Expressway and National Route 4 are anticipated from 6 p.m.

Travelers are being advised to avoid any nonessential outings and continually monitor weather and road information for updates, according to a spokesperson for the ministry, who asked not to be named due to ministry guidelines.

While the Chuo, Kan-Etsu, and Joban expressways are not included for now, the ministry warned that they may be shut down if snow accumulates or accidents occur.

The move comes as cold air and low pressure systems are forecast to bring heavy snow to the Kanto and Koshin regions from Tuesday morning until 6 a.m. Wednesday.

In the broader Kanto region, the northern mountainous area is forecast to have up to 30 centimeters of snow along with the Koshin region, which covers Yamanashi and Nagano prefectures, through Wednesday morning.

For the capital, the Meteorological Agency forecast that the west Tama area in western Tokyo could see up to 15 cm of snow, while the capital's 23 wards are expected to receive around 3 cm in the 24 hours through 6 a.m. on Wednesday.

Both the agency and ministry have urged drivers to be cautious on roads, warning of potential travel disruptions, power outages and structural damage. Residents are advised to equip vehicles with winter tires or chains, allow extra travel time and consider alternative routes or remote work options.