Japan: Adverse weather forecast across eastern and northern regions through at least Dec. 7

Adverse weather conditions are forecast across eastern and northern Japan through at least Dec. 7. A cold front is forecast to track across eastern to northern Japan through Dec. 7, bringing heavy rain, lightning, tornadoes, strong wind gusts, and hail. As of early Dec. 7, the Japan Meteorological Agency (JMA) has issued the following weather warnings:

• Orange storm warnings (the middle level on a three-tier scale): western Akita, far southwestern and far northwestern Hokkaido, and western Yamagata prefectures.

• Yellow thunderstorm, gale, heavy rain, and high wave warnings: the rest of the affected area.

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

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.

Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.

Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters. The disruptive weather may cause some delays and cancellations at airports. Flooding could block regional rail lines; freight cancellations are possible in areas with heavy rainfall and potential track blockages.

Localized business disruptions may occur in areas impacted by severe weather; some businesses might not operate at full capacity because of damage to facilities, possible evacuations, and some employees' inability to reach work sites.