Tournament organisers will inspect the International Stadium in Yokohama at 06:00 local time on Sunday (22:00 BST on Saturday) and make a decision on whether or not it is safe to play the crucial Pool A game, with an announcement to be made two hours later.
If the match is to go ahead, officials will then inspect the state of transport links to decide if it is safe for fans to attend.
If the transport links are not deemed suitable then the match would be played behind closed doors. Calling the game off remains an option.
Sunday’s match – which Scotland have to win to have any chance of qualifying for the quarter-finals – is in the balance as Super Typhoon Hagibis prepares to wreak havoc across Japan’s eastern coast.
World Rugby has already called off two of Saturday’s matches, including England’s game against France which was due to take place at the same stadium as Scotland’s fixture.
If the match is declared a draw then Japan will finish top of Pool A, Ireland will more-than-likely be runners-up and Scotland would then be out of the tournament.
Scotland have demanded contingency plans be put in place for them to compete for a quarter-final place, and have sought legal advice on the matter, but World Rugby has made it clear that rescheduling the match is not an option.