A powerful typhoon is headed toward Japan's southern Pacific coast and is likely to rip through western Japan on Tuesday, with the national weather agency warning it may be the strongest typhoon to make landfall in 25 years.

The Japan Meteorological Agency said a wide area of Japan should be on high alert for strong winds, high waves and heavy downpours.

As of 6 p.m. Monday, Typhoon Jebi was traveling north around 320 kilometers south-southeast of Tanegashima Island at a speed of 20 kilometers per hour, with an atmospheric pressure of 945 hectopascals at its center and packing winds of up to 216 kph, according to the agency.

Categorized as "very strong" by the agency based on the strength of its top winds, Jebi would be the strongest typhoon to make landfall in Japan since 1993 if it maintains its force, an agency official said at an emergency press conference.

• Monsoon rains to persist after Jebi's exit, warns PAGASA

"Rainstorms will likely intensify suddenly as the typhoon is approaching while picking up speed," the official said, urging people not to go out unless necessary and prepare for evacuation.

Japan has been hit by a succession of typhoons recently, with western parts of the country devastated by massive flooding and landslides that left more than 220 people dead.

The weather agency has called for vigilance against flooding, mudslides and high tides caused by this typhoon as well.

Fearing potentially massive damage, airline companies and railway operators are expected to cancel services on Tuesday.

At least 500 flights in western and central Japan are expected to be canceled.

All Nippon Airways Co. expects to cancel 229 domestic flights, and Japan Airlines Co. 117 flights, many being to and from Osaka.

And Skymark Airlines Inc. and Fuji Dream Airlines Co. expect to cancel 52 and 38 flights respectively.

Railway services in areas most affected by the storm will also be severely affected.

West Japan Railway Co. said it plans to halt train services Tuesday, including over 240 limited express train runs. Shikoku Railway Co., Keihan Electric Railway Co. and Nankai Electric Railway Co. will also suspend all or part of their train services.

USJ Co., the operator of Universal Studios Japan in Osaka, also announced it be closed all Tuesday because of the storm.

Prime Minister Shinzo Abe told a meeting of the government and ruling parties, "We have seen typhoons and torrential rains. The government will do its utmost to prevent disaster."

After making landfall somewhere on the main island of Shikoku or Kii Peninsula on Tuesday, the typhoon is expected to pass over the Sea of Japan, the agency said, adding that it will likely weaken to an extratropical cyclone there.

The agency said strong gusts of up to 216 kph could hit the Shikoku and Kinki regions, and gusts of up to 162 kph could affect a wide area including the Tohoku, Tokai and Hokuriku regions.

The Tokyo metropolitan area may see strong winds, though the typhoon is unlikely to pass close to the capital.

Up to 150 millimeters of rain may fall in some regions in western and central Japan through Tuesday morning, the agency said.