Japan: Adverse weather forecast across most of the country through at least June 29

Severe weather is forecast across most of Japan through at least June 29. As of early June 28, the Japan Meteorological Agency (JMA) has warned of heavy rainfall and thunderstorms across western and eastern Japan through at least June 29. Extremely heavy rain is ongoing in Shizuoka Prefecture; the risk of life-threatening landslides and flooding is rapidly increasing. Forecast models indicate rainfall of 20 cm (8 inches) across the Tokai and Kinki regions, 18 cm (7 inches) in the southern Kyushu region, and 15 cm (6 inches) in Shikoku and northern Kyushu regions through early June 29, 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): Kagoshima and western Shizuoka prefectures.

• Red heavy rain, flood, and landslide warnings: eastern Aichi, western Ehime, and northeastern Shizuoka prefectures.

• 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 Iwata and Hamamatsu cities in Shizuoka Prefecture. Evacuation orders for the elderly and vulnerable are in place for parts of Kumamoto and Oita prefectures. JR Kyushu has canceled some train services June 28, including trains on parts of the Hisatsu, Ibusuki-Makurazaki, Kagoshima Main, Kirishima, Nippo Main, and Yoshito lines.

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.