Tropical Storm Ampil is expected to intensify into a typhoon as it nears eastern Japan on Friday, disrupting public transit during the Bon holiday — one of the country’s busiest travel periods.

The storm is projected to approach the Izu Islands, and the Kanto and southern Tohoku regions, with significant force, peaking in intensity between Friday and Saturday.

Central Japan Railway announced Wednesday that it will suspend all Tokaido Shinkansen trains between Tokyo and Nagoya on Friday and warned of possible planned suspensions, service interruptions and delays on the line on Saturday. East Japan Railway has also warned of the possibility of cancellations on the Tohoku, Hokuriku, Joetsu, Akita and Yamagata Shinkansen lines, as well as local lines running in the Kanto region.

Flights to and from Haneda and Narita airports may be canceled, and sections of highways could face closures.

The Meteorological Agency has issued warnings for strong winds, high waves and heavy rain, urging the public to take precautions.

As of Wednesday afternoon, Ampil was moving northeast at 15 kilometers per hour, positioned about 150 km west-southwest of Chichijima island of the Ogasawara Islands. The storm had a central pressure of 975 hectopascals, maximum sustained winds of 108 kph and gusts of up to 162 kph.

On Friday, the current forecast shows the storm strengthening, with expected sustained winds of 144 kph and gusts of up to 216 kph in the Izu Islands and Kanto, and gusts of 126 kph in the Tokai and Tohoku regions. Wave heights could reach 11 meters in Kanto, 10 meters in the Izu Islands, 7 meters in Tohoku and 6 meters in Tokai.

Rainfall forecasts predict up to 200 millimeters in the Kanto-Koshin region and 150 mm in the Tokai region in the 24 hours up to 6 a.m. on Friday, with similar amounts expected in the 24 hours up to 6 a.m. Saturday.

The exact path of the storm remains unclear, with landfall in Chiba Prefecture one possibility. The storm could also pass by the region over the ocean, but it would still bring the threat of torrential rain and violent winds.