Super Typhoon Hagibis is currently on course to affect England's rugby world cup meeting with France in Tokyo on Saturday.
The 170mph storm seems set to make landfall in southern Japan by Saturday and England's Pool C fixture in Yokohama could be hit.
Scotland's Pool A clash with hosts Japan at the International Stadium, Yokohama on Sunday could also be affected by the storm.
Ireland's match against Samoa in Fukuoaka on Saturday and Wales' Pool D fixture against Uruguay in Kumamoto on Sunday currently looks less likely to face disruption.
World Rugby said in a statement it had "robust continency plans" in place should the typhoon hit the weekend pool matches.
Hagibis is currently over the Pacific Ocean and the Met Office's latest estimation is that it will reach southern Japan on Saturday. That could also have an impact on the Japanese Grand Prix at Suzuka.
A Met Office spokesperson said: "There's still a lot of discrepancy about where it will track, and where we'll see the worst impacts.
"It currently is about 200 miles west of the Northern Mariana Islands. It has an estimated wind speed of 120mph and gusts of around 170mph. It's continuing to head northwards towards mainland Japan.
"It is expected to weaken before it reaches landfall and at the moment there is still some discussion about where it might reach landfall. It looks like being towards the weekend, Saturday potentially.
"It looks like there will still be sustained wind speeds of 100mph when it reaches landfall but it's exact path is uncertain.
"We are expecting very heavy rain as well. We are certainly looking, depending on where it hits, at the potential for flash flooding and wind damage."
A statement from World Rugby read: "World Rugby, Japan Rugby 2019 and our weather information experts continue to closely monitor the direction and strength of Typhoon Hagibis (Typhoon 19).
"It remains too early to fully predict the movement and impact of the storm, however the latest modelling by our weather information experts indicates that it is now tracking north and east and will bring strong winds and heavy rain to Tokyo and surrounding areas on 12 October.
"Public and team safety is our number one priority. While we have robust continency plans in place for pool matches, such plans, if required, will only be actioned if the safety of teams, fans, and workforce can be guaranteed. It would be inappropriate to comment on any contingency plans at this stage.
"We will continue to closely monitor this developing situation in partnership with our weather information experts, local authorities, transport providers and the teams, and will provide a further update tomorrow. Fans are advised to monitor official Rugby World Cup channels for any updates."
Hagibis escalated from a tropical storm into a Category 5 super typhoon in one of the most dramatic intensifications of any tropical cyclone since records began.
Such storms can fade and change direction and there have already been false alarms at this World Cup, while Formula One ruling body the FIA is also monitoring the situation ahead of Sunday's race.
Any World Cup matches cancelled due to weather problems are registered as scoreless draws and would have no impact on the final standings for England and France as both have already qualified for the quarter-finals.
England attack coach Scott Wisemantel said: "We have no control over the weather and we have to prepare for the game and see how it goes.
"Regarding the permutation around the game and shared points, we are just concentrating on playing to win.
"I live in a bubble and I don't know where the game would be played (if it is called off).
"One thing I have learnt in Japan is that they prepare for the worst and then usually it doesn't eventuate."
