TOKYO - Heavy rain continued across wide areas of Japan on September 9 after downpours began the previous day, prompting Level 4 flood danger warnings along several rivers in Tokyo and, at one point, a Level 5 emergency safety alert in Nagoya, while forecasters warned that another round of intense rain could hit the Kanto region during the afternoon and evening.
Warm, humid air flowing into a weather front brought heavy rain across much of Kanto on September 8, with Hachioji in western Tokyo recording 49.5 millimeters of rain in one hour.
Reports from Hachioji showed flooded roads in parts of the city as active rain clouds passed over the region during the evening.
A Level 4 heavy rain danger warning was temporarily issued for Moka, Tochigi Prefecture.
In Tokyo, rising water levels prompted Level 4 flood danger warnings for the Zenpukuji River, the Nogawa and Sengawa rivers, and the Shakujii River.
Near the Zenpukuji River in Suginami Ward, one resident said the water level had risen considerably. "I came to check because I may have to move my car," the resident said. "I hope the water level comes down soon."
Forecasters said the front responsible for the previous day's intense rain had temporarily moved north of the Kanto plains but was expected to return southward during the evening of September 9, bringing another period of potentially severe weather.
A tropical depression was located near Tokushima Prefecture and could transition into a low-pressure system, with its circulation and accompanying active rain clouds expected to move toward eastern Japan.
While relatively little heavy rain was expected across the Kanto plains during the earlier part of the day, stronger rain was forecast to spread into the region toward evening, including across urban areas.
Thunderstorms and intense downpours were possible as the front crossed southern Kanto, including central Tokyo.
The main peak of rain in southern Kanto was expected at around 5 p.m. on September 9.
Forecast charts indicated that the center of the low-pressure system would move from the Tokai region toward the vicinity of Shizuoka Prefecture during the evening.
The front extending eastward from the low was expected to pass across southern Kanto around the evening before moving farther south late at night toward an area stretching from Izu Oshima to waters south of the Boso Peninsula.
Rain was expected to ease somewhat across the Kanto plains after the front moved south, but strong rain could continue in southern Chiba Prefecture and parts of northern Kanto as the main low-pressure system approached.
Forecasters also warned that winds in central Tokyo could shift sharply as the front passed. Southerly winds during the daytime were expected to bring unusually hot and humid conditions, before turning northeasterly at night and causing temperatures to fall rapidly.
Residents were advised to prepare for a noticeably cooler evening despite the muggy daytime conditions.
Authorities also warned that the evening commute could coincide with the strongest rain, raising the risk of road flooding and other transport disruptions.
Even in areas where rainfall temporarily subsides, dangerous conditions could return as new rain clouds develop or the front shifts position.
Rainfall totals forecast through the morning of September 10 are up to 120 millimeters in Kanto-Koshin and Hokuriku, 200 millimeters in Tokai and Kinki, and 150 millimeters in Shikoku.
Forecast information warning of the possible formation of linear rainbands has also been issued for the Tokai, Kinki and Shikoku regions.
Authorities are urging residents to remain on high alert for landslides, flooding in low-lying areas and rapidly rising rivers, and to continue checking the latest weather information through the evening.
Source: ウェザーニュース
