Japan: Adverse weather forecast across most of the country through at least June 19

Severe weather is forecast across most of Japan through at least June 19. As of early June 18, the Japan Meteorological Agency (JMA) has warned that heavy rainfall across the Shikoku region is likely to continue through at least early June 19. Very heavy to torrential rain with thunderstorms is forecast in the Ryukyu Islands as well as from western to eastern Japan June 18. Forecast models indicate rainfall of 25 cm (10 inches) across the Tokai region, 20 cm (8 inches) in the Kanto, Koshin, and Shikoku regions, and 15 cm (6 inches) in the Kinki region through early June 19, with lesser amounts of rainfall through the rest of Japan.

The JMA has issued the following weather warnings across the affected area:

• Purple landslide warnings (the highest level on a three-tier scale): Okinawa Main Island in Okinawa Prefecture.

• Red heavy rain, flood, and landslide warnings: eastern Ehime, northern Nara, and northern Wakayama prefectures as well as Kume Island in Okinawa Prefecture and Amami Region in Kagoshima Prefecture.

• Yellow warnings: Across most of the rest of the affected area.

Officials will likely issue new alerts or update/rescind existing advisories as weather conditions develop over the coming days.

Authorities have issued evacuation orders for tens of thousands of residents in Itoman, Naha, Nago, Okinawa, Tomigusuku, Urasoe, and Uruma cities, Ginoza, Ogimi, Onna, and Yomitan villages, Kadena Town in Okinawa Prefecture, and parts of Kozagawa Town in Wakayama Prefecture. Evacuation orders for the elderly and vulnerable are in place for Ginowan and Nanjo cities as well as Kin and Nishihara towns in Okinawa Prefecture. Some Kirishima train services in Kyushu are suspended due to heavy rain. JR West has canceled train services on the Kansai Line connecting Kameyama Station in Mie Prefecture to Kamo Station in Kyoto Prefecture, Kakogawa Line between Nishiwakishi and Tanigawa stations, and Wakayama Line between Takada and Hashimoto stations, while JR Shikoku has suspended services on the Mugi Line between Anan and Awa-Kainan stations in Tokushima Prefecture early June 18. JR East has warned of possible delays, changes in destinations, and cancellations of train services on the Tokaido Line between Odawara Station in Kanagawa Prefecture and Atami Station in Shizuoka Prefecture and on the Ito Line between Atami and Ito stations through the evening of June 18.

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where heavy rain has saturated the soil. Disruptions to electricity and telecommunications services are likely where significant flooding, landslides, or strong winds impact utility networks.

Floodwaters and debris flows will likely render some bridges, rail networks, or roadways impassable, impacting overland travel around affected areas. Ponding on road surfaces will probably cause hazardous driving conditions on regional highways. Authorities will likely temporarily close some low-lying routes that become inundated by floodwaters.

Severe weather will also probably cause intermittent flight delays and cancellations at airports across the affected region, though these are unlikely to be severe or prolonged. Authorities will likely suspend port operations or close beach fronts temporarily if strong winds trigger hazardous sea conditions. Flooding will probably block regional rail lines; freight and passenger train delays and cancellations are likely in areas with heavy rainfall and potential track inundation. Localized business disruptions are probable in low-lying areas.