With heavy snow forecast to fall across a wide area of the Kanto region from Friday morning, officials on Thursday urged those in affected areas to refrain from nonessential outings and warned of transport disruptions and the risk of blackouts.

On Thursday, officials from the Meteorological Agency said snow is expected to fall in the Kanto-Koshin region starting Friday morning, with heavy snow expected mainly in mountainous areas. But some accumulation is also expected in low-lying areas — including central Tokyo.

By the afternoon, the snow is expected to turn to rain in many areas, especially areas near the Pacific coast. But small changes in temperature can mean the difference between rain and snow, and a later transition to rain could lead to a warning-level snow event, including in low-lying areas.

Heavy snow warnings could prompt local officials to take actions such as canceling or delaying schools, among other steps, but exact measures would differ by municipality.

Even areas where the snow turns to rain could see low temperatures on Saturday morning, with officials urging the public to watch for icy roads. The snow could also cause electricity poles to fall, causing power outages.

On Friday, traffic could be backed up during the morning rush hour, officials said, and conditions could worsen by the time people are aiming to return home. In areas with heavy snow, officials encouraged people to adjust their commute times or work remotely, calling on companies to allow remote work even if that’s normally not an option.

Depending on snowfall conditions and other factors, expressways could be closed across wide areas, and national routes running parallel to expressways could also face closures.

Public transit networks could also face extensive, prolonged delays or suspensions, officials warned.

Officials called on residents to check the latest warnings and advisories online, as conditions can change rapidly.

“It’s difficult to say an exact time when the snow will change into rain,” the Meteorological Agency’s Toru Ikeda said Thursday.

“One thing people can do is not go home via car for safety,” said Naoki Terasawa, an official from the transport ministry. “Some people have been trapped in their cars in the past due to heavy snow, and we’d like to avoid that.”

In late January, heavy snow in central Japan left vehicles stuck on an expressway in Shiga and Mie prefectures for more than a day, echoing similar events across other parts of the country in recent years.

Those who have no choice but to drive are asked to use winter tires, carry chains and install them as soon as possible, and carry equipment such as shovels and sand.