Japan Rugby World Cup Monthly Rainfall and Temperature Outlook

Updated: 2 October 2019



The Rugby World Cup is well underway. The September forecast has played out very well with some rain where expected and warmer than normal temperatures. Last month’s Typhoon Tapah that transformed to a tropical storm near Japan brought some rain to the southern and western part so the country. Fast forward a couple of weeks and now discussion is around tropical storm Mitag that is looking like it will follow a similar path to Tapah moving up the western side of the country in the Sea of Japan. As Mitag continues north-eastward and is likely to remain offshore but will be bringing rain to the southern, western and northern part of the country for the next few days.

The final outlook for October is in. After a rainy and warm September, it looks like it could remain wetter and warmer than normal across all the RWC stadia through the rest of the tournament.

Latest October through November Rainfall Outlook Percentage Change from Historical (forecast released 2 October 2019)

Rainfall Synopsis

Historical October rainfall across all the venue ranges from 177 mm at Shizuoka Stadium Ecopa located in Fukuroi City located about 240 km southwest of Tokyo. Most venues average around 115 to 160 mm for the month.

The outlook for October however is for wetter than normal conditions for all venues. Kobe Masaki Stadium could be about 30 percent wetter than normal for the month. Most of the other venues could be between 10 and 25 percent wetter than normal. Kamaishi Recovery Memorial Stadium is possibly closest to normal with just over 4.0 percent more rainfall than normal. Sapporo Dome is the only drier that normal venue with about 22 percent of normal rainfall.

November rainfall on average decreases from the highs in September and October. However, the seasonal outlook for November looks wetter than normal for International Stadium (currently forecast to be 23 percent wetter than normal for the month) the host of the final match. We will continue with the outlook for the finals venue with the next release of data in 10 days.

Latest October through November Temperature Outlook Percentage Change from Historical (forecast released 2 October 2019)

Temperature Synopsis

Historical October MEAN temperatures across all the venue ranges from 11.0 degrees C at the Sapporo Dome in Hokkaido to 18.6 degrees C for Shizuoka Stadium Ecopa. For most venues MEAN average temperature is in high teens Celsius for the month. Note that these are the average MEAN temperatures not the average high or low temperatures for the month.

The outlook for October is for the MEAN temperature to be warmer than normal for all venues. With City fo Tokyo Stadium possibly averaging over 1.8 degrees C above normal for the month. Most of the venues are in the 1.4 to 1.8 degree C above average range. In general, the month of November is also likely to be warmer than normal but close to 1.0 degrees C.

We will continue with the outlook for the finals venue with the next release of data in 10 days.

Japan Rugby World Cup Monthly Rainfall and Temperature Outlook

Updated: 23 September 2019



The Rugby World Cup is underway. The September forecast we released has been playing out well so far. With rain in the west and warmer than normal temperatures. This past weekend Typhoon Tapah has brought some rain to the southern part of Japan. It is likely to move up the western side of the country in the Sea of Japan. As Tapah continues north-eastward and is likely to remain offshore but will be bringing rain to the western and northern part of the country for the next few days.

The forecast for October is settling in. After a rainy and warm September it looks like it could be drier and warmer than normal across the whole country.

Latest October through November Rainfall Outlook Percentage Change from Historical (forecast released 21 September 2019)

Rainfall Synopsis

Historical September rainfall across all the venue ranges from 142 mm at Shizuoka Stadium Ecopa located in Fukuroi City located about 240 km southwest of Tokyo. Most venues average around 120 to 160 mm for the month.

The outlook for September however is for drier than normal conditions for all venues. Sapporo Dome where rainfall is not so critical could be about 25 percent drier than normal for the month. Most of the other venues could be between 10 and 20 percent drier than normal. Kobe Misaki Stadium is possibly closest to normal with nearly 8.0 percent less rainfall than normal.

November rainfall on average decreases from the highs in September and October. However, the seasonal outlook for November looks wetter than normal for International Stadium the host of the final match. We will highlight specifics about October and the finals venue with the next release of data on 2 October.

Latest October through November Temperature Outlook Percentage Change from Historical (forecast released 21 September 2019)

Temperature Synopsis

Historical September MEAN temperatures across all the venue ranges from 11.0 degrees C at the Sapporo Dome in Hokkaido to 18.6 degrees C for Shizuoka Stadium Ecopa. For most venues MEAN average temperature is in high teens Celsius for the month. Note that these are the average MEAN temperatures not the average high or low temperatures for the month.

The outlook for October is for the MEAN temperature to be warmer than normal for all venues. Only Oita Stadium is likely to be close to normal. With Kamaishi Recovery Memorial Stadium in Kamaishi City possibly averaging over 1.4 degrees C above average for the month. Most of the venues are in the 1.2 to 1.3 degree C above average range. In general, the month of November is also likely to be warmer than normal.

The final outlook for October temperatures will be released on 2 October and an outlook for the final in November as well.

Japan Rugby World Cup Monthly Rainfall and Temperature Outlook

Updated: 12 September 2019



The Rugby World Cup is set to start with the Japan versus Russia clash on Friday the 20th of September at Tokyo Stadium.

There has been a lot of discussion in the media about what the weather might be like and how it could influence the tournament. With venues stretched across the island nation from the Sapporo Dome in Hokkaido in the north to Kumamoto Stadium in Kyushu in the south we are looking at nearly 1500 kilometres (or close to 900 miles) of diverse geography in between. Over the life of the tournament we can expect a range of weather conditions.

Four of the venues have either a permanent roof such as the Sapporo Dome or retractable roofs: City of Tokyo Stadium, Kobe Misaki Stadium or Oita Stadium. That leaves the remaining eight venues and the teams and fans exposed to the elements in the case of inclement weather.

Planning for the weather is something all teams and fans do. Regular weather forecasts for game day are available from multiple sources. The team at CLIMsystems and ExtendWeather fill an important gap by providing month by month outlooks so that longer term planning can be considered.

The RWC is being played during typhoon season. Predicting the risk of a typhoon months in advance is not possible but foreseeing how much warmer/colder or wetter/drier than normal conditions may prevail is possible.

We have already seen teams adjust their training schedules owing to warmer than normal conditions this September. How might those conditions change in October and November? That is why we will be generating outlooks that we will update approximately every ten days during the RWC.

September through November Rainfall Outlook Percentage Change from Historical (outlook released 2 September 2019)

Rainfall Synopsis

Historical September rainfall across all the venue ranges from 142 mm in Kumagaya Rugby Stadium to the northwest of Tokyo to a high of 259 mm at Shizuoka Stadium Ecopa located in Fukuroi City located about 240 km southwest of Tokyo. Most venues average around 200 to 250 mm for the month.

The outlook for September however is for wetter than normal conditions for most venues. Fukuoka Hakatanomori Stadium could be up to 14 percent wetter than normal. Most of the other venues could be between 8 and 10 percent wetter than normal. City of Toyota Stadium should be near normal while only the International Stadium and Shizuoka Stadium Ecopa could be drier than normal.

October and November rainfall on average decreases from the highs in September. However, the seasonal outlook for both months is for wetter than normal conditions in both months and for November considerably wetter than normal conditions for some areas. We will highlight specifics about October and the finals venue with subsequent seasonal outlooks.

September through November Temperature Outlook Degrees Celsius Change from Historical (outlook released 2 September 2019)

Temperature Synopsis

Historical September MEAN temperatures across all the venue ranges from 17.5 degrees C at the Sapporo Dome in Hokkaido to 24.0 degrees C for Ōita Stadium Ōita Prefecture on Kyushu Island located about 760 km southwest of Tokyo. For most venues MEAN average temperature is in low 20s Celsius for the month. Note that these are the average MEAN temperatures not the average high or low temperatures for the month.

The outlook for September is for the MEAN temperature to be warmer than normal for all venues. Only Oita Stadium is likely to be close to normal. With Kamaishi Recovery Memorial Stadium in Kamaishi City possibly averaging over 1.1 degrees C above average for the month. Most of the venues are in the 0.7 to 1.0 degree C above average range. In general, the month of September is as we have already been hearing likely to be warmer than normal.

As expected, October and November monthly average temperatures decrease slowly, however the longer-range outlook is for both months to be warmer than normal. The outlooks for these months will be highlighted in subsequent seasonal forecasts.