TOKYO — Japanese railways and airlines are canceling services as Typhoon Ampil gathers strength in the western Pacific, with the storm expected to hit on Friday during the peak summer travel season.

As of early Thursday local time, Typhoon Ampil was recording sustained winds of 140 kph (85 mph), according to the latest advisory from the Joint Typhoon Warning Center (JTWC). That makes it the equivalent of a Category 1 hurricane in the Atlantic basin.

And it’s likely to strengthen further in the next 36 hours, since the storm is moving over very warm water – meaning more moisture in the air to fuel the typhoon. By Friday evening, as it nears Japan southeast of Tokyo, it could become the equivalent of a Category 3 hurricane, according to a JTWC forecast.

Two major airlines, Japan Airlines and All Nippon Airways, canceled about 500 flights in total serving the capital’s Haneda and Narita airports, according to public broadcaster NHK.

Rail travel has been disrupted too. Six lines on Japan’s extensive bullet train network are suspending services between certain stations and warning of major delays on Friday – including the important Tokaido line that connects Tokyo with Osaka.

Japan’s meteorology officials have warned that some parts of northern and eastern Japan may see violent winds, rough seas, heavy rain, flooding, landslides and overflowing rivers, according to NHK. They urged the public to exercise caution and stay prepared.

The storm’s center is expected to remain slightly offshore as it turns toward the northeast and moves away from Japan, according to JTWC and Japan’s Meteorological Agency. If it stays offshore and only brushes the coast, it might only have a light impact on Japan, bringing rain and wind to some areas including Tokyo.

However, it could have a much stronger effect if the direction changes to bring the center closer to the coast, or even makes landfall.

The storm is expected to weaken by Saturday morning local time and die down as it moves into cooler waters over the weekend. — CNN