06 Oct 2023 | 01:52 AM UTC
Japan: Adverse weather forecast across the northern regions through at least early Oct. 7
Severe weather forecast across northern Japan through at least early Oct. 7. Flooding, landslides, and associated disruptions likely.
Event
Severe weather is forecast across northern Japan through at least early Oct. 7. As of early Oct. 6, the Japan Meteorological Agency (JMA) has warned of extremely strong winds, high waves, landslides, and flooding rivers in northern Japan and severe storms at sea. High tides are likely in Hokkaido. Strong wind gusts, lightning, hail, and possible tornadoes may accompany storms. Rainfall totals of around 12 cm (4.7 inches) in the Hokkaido region and 8 cm (3 inches) in the Tohoku region are forecast through early Oct. 7.
The JMA has issued purple (the highest level on a three-tier scale) storm surge warnings across far northeastern Hokkaido Prefecture and red heavy rain/inundation, storm, and high wave warnings across northern and southern Hokkaido, Aomori, Akita, western Yamagata, eastern Miyagi, and northeastern Iwate prefectures. Yellow advisories are in place across 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.
A tornado occurred in Kurobe City, Toyama Prefecture, early Oct. 5, damaging at least seven buildings and three vehicles. Approximately 440 homes in Iku and Iku Ashizaki, Kurobe City were temporarily without power. In Niigata Prefecture, strong winds damaged another six buildings in Seiko Town and three buildings in Shibata City early Oct. 5. Overhead line problems delayed some trains on the Tohoku Shinkansen.
Sustained heavy rainfall will likely trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also probable 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 likely in hilly or mountainous areas, especially where heavy rainfall has saturated the soil. Strong winds may cause property damage and power outages.
Authorities will probably issue evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are likely where significant flooding or landslides impact utility networks.
Floodwaters and debris flows will likely 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.
Severe weather will probably trigger flight delays and cancellations at airports in the affected areas. Flooding could 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 will likely occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, evacuations, and some employees' inability to reach work sites.
Advice
Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.
