Japan: Adverse weather ongoing across Iwate Prefecture as of the afternoon of Aug. 12

Event

Severe weather is forecast across Iwate Prefecture through at least Aug. 13. Strong wind gusts, lightning, hail, and possible tornadoes may accompany storms. Heavy downpours could trigger flooding in low-lying areas and landslides on unstable slopes. Strong winds may cause property damage and power outages. As of the afternoon of Aug. 12, the Japan Meteorological Agency (JMA) has issued purple heavy rain and landslide warnings (the highest level on a three-tier scale) and red flood warnings across most of Iwate Prefecture. Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions develop over the coming days.

Authorities have issued evacuation orders for more than 7,000 people in Tono City. At the height of the storm, around 1,400 households in Iwate Prefecture were without power; most power has since been restored. As of early Aug. 12, around 200 households in Hanamaki, Miyako, and Ninohe cities were without power. JR East has suspended train services on the Kamaishi Line between Hanamaki and Kamaishi stations. A landslide early Aug. 12 has resulted in the closure of a local road in Kirikiri, Otsuchi Town.

Hazardous Conditions
Sustained heavy rainfall could trigger additional flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also likely 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.

Authorities could issue additional 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.

Transport
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 could also 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 that see 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.

Resources

Japan Meteorological Agency