11 Jul 2023 | 09:46 AM UTC
Japan: Severe weather forecast to continue across much of the country through at least July 13 /update 2
Severe weather forecast across much of Japan through at least July 13. Weather-related disruptions ongoing in southwestern regions.
Event
Severe weather is forecast to continue across much of Japan through at least July 13. As of July 11, the Japan Meteorological Agency (JMA) has warned that a weather front will create unstable conditions from northern to western Japan in the coming days. Heavy rainfall and thunderstorms are expected across much of the country; storms may be accompanied by strong wind gusts, lightning, hail, and possible tornadoes. Rainfall totals of around 12 cm (5 inches) are forecast in Hokuriku and Tohoku regions late July 12-13. 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 July 11, the JMA has issued the following weather warnings across the country:
Red heavy rain/inundation warnings (the middle level on a three-tier scale): Ishikari, Kamikawa, and Sorachi regions in Hokkaido Prefecture.
Red heavy rain/landslide warnings: Parts of Toyama Prefecture in Hokuriku Region.
Red flood warnings: Ishikari Region in Hokkaido Prefecture.
Yellow heavy rain/inundation warnings: Abashiri, Kitami, Mombetsu, Shirbeshi, and Tokachi regions in Hokkaido Prefecture and parts of Nagasaki Prefecture in Northern Kyushu Region.
Yellow heavy rain/landslide warnings: Kitami and Mombetsu regions in Hokkaido Prefecture; parts of Akita, Aomori, Iwate, Fukushima, and Yamagata prefectures in Tohoku Region; parts of Ibaraki and Tochigi prefectures in Kanto Koshin Region; parts of Gifu Prefecture in Tokai Region; across Shimane Prefecture in Chugoku Region; and parts of Fukuoka, Nagasaki, Oita, and Yamaguchi prefectures in Northern Kyushu Region.
Yellow flood warnings: Kamikawa, Mombetsu, Rumoi, Shiribeshi, Sorachi, and Toakchi regions in Hokkaido Prefecture; parts of Aomori Prefecture in Tohoku Region; and parts of Nagasaki Prefecture in Northern Kyushu Region.
Yellow storm gale warnings: Parts of Chiba, Kanagawa, and Tokyo prefectures in Kanto Koshin Region; parts of Niigata Prefecture in Hokuriku Region; and parts of Fukuoka, Nagasaki, Saga, and Yamaguchi prefectures in Northern Kyushu Region.
Yellow high wave warnings: Parts of Chiba, Kanagawa, and Tokyo prefectures in Kanto Koshin Region.
Yellow storm surge warnings: Parts of Hyogo Prefecture in Kinki Region.
Yellow thunderstorm warnings: Across most of the country.
Yellow dense fog warnings: Across Hokkaido Prefecture, across Aomori Prefecture in Tohoku Region, and across Chiba and Ibaraki and parts of Tokyo prefectures in Kanto Koshin region.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions develop over the coming days.
Disruptions are ongoing across parts of southwestern Japan following days of adverse weather. As of July 11, authorities have reported at least five fatalities and three others missing across Fukuoka, Oita, and Saga prefectures in Northern Kyushu Region. The Kyushu Railway Company has warned of widespread disruptions to rail services across the region; the latest information regarding the status of trains in Kyuhsu can be found here. Sections of the Oita Expressway in Asakura City, Fukuoka Prefecture, have been closed due to a landslide. Floodwaters have damaged the Yabakei Bridge, which spans the Yamakuni River in Nakatsu City, Oita Prefecture. At least 13 landslides have been reported across the affected area since July 9 and around 18 rivers have burst their banks. Multiple houses were damaged by a landslide in Kurume City, Fukuoka Prefecture July 10. At least six hospitals in Fukuoka Prefecture have reported flood damage and landslides have led to water supply cust in Okagaki Town. Some mobile network services in the affected area have also been affected by adverse weather.
Disruptions and weather-related damage have also been reported across other parts of the country as of July 11. Several homes and businesses were damaged by strong winds in both Nogi Town, Tochigi Prefecture, and Shimotsuma City, Ibaraki Prefecture, in Kanto Koshin Region late July 10. A section of the Sanin Expressway in Izumo City, Shimane Prefecture, in Chugoku Region was closed since July 9 due to damage likely caused by heavy rain. Heavy rainfall and thunderstorms in Hokkaido Prefecture July 11 have led to the cancelation of at least 21 trains across the prefecture, as well as power outages in some areas.
Hazardous Conditions
Sustained heavy rainfall could trigger 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 located 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.
