According to the Japan Meteorological Agency (JMA), Typhoon Shanshan, as of 9:00 p.m. local time was some 330 kilometers east-southeast of Hachijo Island of the Izu Island chain and moving at a speed of 20 km per hour in a north-northwesterly direction.
The agency said the storm has an atmospheric pressure of 970 hectopascals and is packing winds with speeds of up to 126 kilometers an hour near its center.
This year's 13th typhoon will bring torrential rain to the Pacific coastal side of eastern and northern Japan, the JMA said, as it approaches the Izu Islands on Wednesday and hits the main island of Honshu thereafter.
The storm has already caused the weather agency to issue flood and landslide warnings and the JMA has forecast that for the 24-hour period through Wednesday afternoon, 150 millimeters of rain will likely fall in eastern and central Japan, with as much as 400 mm has been forecast to fall in the 24 hour period thereafter.
On Thursday, Typhoon Shanshan's trajectory will likely take it in a northerly direction along the Pacific coast of northeastern Japan.
Transportation authorities have already taken preemptive measures prior to the typhoon's full impact, with All Nippon Airways (ANA) cancelling its six flights Wednesday between Tokyo's Haneda airport and Hachijo Island.
Budget carrier Jetstar, meanwhile, has cancelled 19 of its domestic flights.