10 Oct 2022 | 10:14 AM UTC
Japan: Adverse weather forecast across Hokkaido Prefecture through at least Oct. 11
Severe weather forecast across Hokkaido Prefecture, Japan, through at least Oct. 11. Possible flooding, landslides, and disruptions.
Event
A weather front is forecast to bring severe weather across Hokkaido Prefecture through at least Oct. 11. The weather system will bring heavy rainfall, strong winds, thunderstorms, and rough seas as it passes over the region. Rainfall totals of around 6 cm (2.4 inches) are forecast across much of Hokkaido late Oct. 10-late Oct. 11, with isolated totals of up to 12 cm (4.7 inches) possible. Winds of around 83 kph (52 mph), with gusts of up to 126 kph (78 mph), are expected in the affected region, as well as waves of around 5-6 meters (16-20 feet) in coastal areas.
As of Oct. 10, the Japan Meteorological Administration has issued the following weather warnings across Hokkaido Prefecture:
Red warnings for heavy rainfall and landslides: Iburi and Oshima regions.
Red flood warnings: Iburi and Tokachi regions.
Red high wave warnings: Hidaka, Kushiro, Nemuro, and Tokachi regions.
Yellow heavy rain, landslide, flooding, thunderstorms, strong winds, high wave, and dense fog advisories: Across much of the rest of Hokkaido.
Yellow storm surge warnings: Kushiro and Oshima regions.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
Authorities have ordered the evacuation of the elderly for around 52 households in Shiraoi town due to rising water levels in the Shibu River. Authorities could order further evacuation orders across parts of Hokkaido as weather conditions deteriorate in the coming hours.
Hazardous Conditions
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 located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides remain possible in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.
Transport
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. Severe weather could also trigger flight delays and cancellations at regional airports. Authorities may temporarily suspend port operations or close beach fronts if strong winds trigger hazardous sea conditions. Flooding could block regional rail lines; freight and passenger train delays and cancellations are possible in areas that see heavy rainfall and potential track inundation.
Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible 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.