19 Jul 2022 | 02:38 AM UTC
Japan: Severe weather forecast over western regions through at least July 20
Heavy rainfall forecast over western Japan, through at least July 20; evacuation orders in place.
Event
Heavy rainfall is forecast to bring a threat of flooding and landslides across Kyushu, Shikoku, and western Honshu through at least July 20. As of early July 19, the Japan Meteorological Administration has issued purple warnings for heavy rain and landslides (the highest level on a three-tier scale) over Fukuoka, western Oita, Saga, Shimane, and most of Yamaguchi prefectures, as well as red heavy rainfall, landslide, and flood warnings across eastern Ehime, Hiroshima, most of Kumamoto, southern Kyoto, Nagasaki, Okayama, western Tottori prefectures. Yellow gale, high wave, thunderstorm, and storm surge warnings have also been issued across the rest of the affected area. A purple flood danger advisory (the second highest level on a four-tier scale) is in place for the upper Yamakuni River in Fukuoka and Oita prefectures; flooding is possible in Nakatsu City, Oita Prefecture and Koge Town, Chikujo District, Fukuoka Prefecture. Yellow flood caution advisories (lowest level on a four-tier scale) are also in place over the Fushino and Niho river systems in Yamaguchi Prefecture, Chikugo River in Fukuoka, Oita, and Saga prefectures, Takatsu River in Shimane Prefecture, and Yabe River in Fukuoka Prefecture. Authorities will likely issue new warnings or update existing advisories in the coming days.
Forecast models indicate 25 cm (10 inches) of rainfall over Kyushu, 20 cm (8 inches) over Shikoku and the Kinki Region, and 10 cm (4 inches) over the Chugoku Region through early July 20. Authorities have advised residents in western Japan, including Kyushu, to be vigilant for possible flooding and landslides through late July 19.
Due to the threat of landslides, authorities have issued evacuation orders for around 410,000 people in Fukuoka, Oita, Saga, Shimane, and Yamaguchi prefectures, advising those in places prone to landslides to evacuate. Authorities may issue additional evacuation orders if weather conditions persist or worsen.
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.
