World Rugby has called a press conference for 4am BST in which an update will be issued on whether England’s World Cup clash with France will be moved or cancelled.
Super Typhoon Hagibis is due to sweep through Tokyo this weekend, affecting the Pool C decider at International Stadium Yokohama on Saturday and also Scotland’s pivotal group showdown against Japan 24 hours later.
The options available to World Rugby are to either cancel the all-Six Nations fixture or move it to Oita, where the quarter-finals are being staged.
With Hagibis due to have moved on by the end of the weekend, Scotland could see their clash with Japan delayed by 24 hours but played at the same venue.
If, as expected, the England game is cancelled or switched to Oita then it would be the first time a World Cup match has been affected in this way in nine instalments of the tournament and it would cause chaos for travelling fans.
It is understood that World Rugby is insured against the lost revenue from two cancelled games.
The sport’s global governing body has refused to outline its plans before the press conference amid conflicting reports over what has been decided.
Any games cancelled due to weather problems are registered as scoreless draws and would have no impact on the final standings as England and France have already qualified for the quarter-finals.
However, the integrity of the tournament would be brought into dispute as the northern hemisphere heavyweights are battling for top spot and entrance into one half of the knockout phase.
But the stakes are far higher for Scotland as, were their clash with Japan to be abandoned without a ball being kicked, they would be eliminated from the World Cup.
The storm which was on Wednesday described by the Japanese Meteorological Agency as “violent” has escalated into a Category 5 super typhoon with winds reaching 180mph in one of the most dramatic intensifications of any tropical cyclone since records began.
It is many times the dimensions of Typhoon Faxai, which brought Tokyo to a standstill for the day of England’s arrival for the World Cup, delaying their exit from Narita Airport by six hours, killing three people and leaving a million homes without power.
Satellite images of the extreme weather event reveal that it is the size of Japan and shows no sign of either deviating from its path or decreasing in magnitude.
Ireland’s Pool A game against Samoa on Saturday and Wales’ Pool D clash with Uruguay on Sunday are on the other side of Japan – in Fukuoka and Kumamoto, respectively – so most likely out of the storm’s main path.
The Japanese Grand Prix at Suzuka, however, could be affected.
A spokesperson for Formula One’s ruling body the FIA said: “As normal we continually monitor the weather at Formula One events and are working with the circuit organisation, the Japanese Automobile Federation and Formula One to react as necessary should any timetable changes be required.
“This is not the first time that inclement weather has been a possibility at the Japanese Grand Prix so the procedures here are well practiced.”
What strength the wind speeds will be once it makes landfall this weekend and the impact of any flooding or tidal surge remains to be seen.
A Met Office spokesperson told the PA news agency: “The overall story remains the same. Typhoon Hagibis in the western North Pacific is on track towards Japan this weekend.
“As of Wednesday morning, it was located around 900 miles south of Tokyo with estimated wind speeds of around 120mph and gusts of 170mph.
“Obviously as Hagibis moves towards Japan it is going to weaken and those wind speeds will fall.
“We are expecting that Hagibis is likely to make landfall on Saturday, not too far from Tokyo.
“By that stage it will have weakened significantly, but with sustained wind strengths still of around 90mph and with gusts of up to 135mph. Along with the strong winds, we are expecting very heavy rain along its path.
“Obviously with those very strong and severe winds, with heavy rain, there is likelihood of significant impact from the damaging winds and also from storm surge.
“With the winds and large waves, there is the risk of flash flooding as well in the Tokyo region.”
The Met Office spokesperson added: “While the location and extent of impact are still rather uncertain, there is an increasing likelihood Hagibis will affect southern Japan.”