Japan’s Meteorological Agency has officially declared the “likely” start of the rainy season across wide swathes of the country, bringing sustained wet weather. Following declarations on Monday for the Tokai, Kinki, and Chugoku regions, Tuesday saw the Kanto-Koshin and Hokuriku regions enter the rainy season. Northern Kyushu and Shikoku began their rainy season on Sunday, the same day the season concluded in Okinawa. Southern Kyushu experienced an unusually early start, with its rainy season commencing on May 16.
The seasonal rain front is predicted to hover over Honshu, delivering successive periods of rainfall to both western and eastern Japan. The front is expected to be particularly active through Wednesday, raising the likelihood of heavy rain in areas including Kanto-Koshin and Hokuriku, with western Japan facing a heightened risk of torrential downpours.
While a temporary weakening of the front is possible after Wednesday, forecasters anticipate it will regain strength around Saturday. This resurgence is expected to coincide with the probable commencement of the rainy season in the Tohoku region. Northern Kyushu experienced especially intense rain on Tuesday morning, prompting the Meteorological Agency to issue a warning about a potential linear rainband later in the day.
Significant rainfall is forecast, with up to 180 millimeters expected in northern Kyushu, 150 mm in the Kinki region, and 120 mm across Chugoku and southern Kyushu in the 24 hours leading up to 6 a.m. Wednesday. An additional 60 mm is anticipated in northern Kyushu between 6 a.m. Wednesday and 6 a.m. Thursday.
With the seasonal rains now firmly established, authorities are urging residents to maintain vigilance for potential landslides, river overflows, and flooding in low-lying areas. Officials strongly advise preparing emergency supplies, identifying multiple evacuation routes away from flood-prone zones, and ensuring gutters and drains are clear of debris to mitigate risks before heavy rainfall commences.
FAQs
Q1: Which regions have entered the rainy season most recently?
A1: On Tuesday, the Kanto-Koshin and Hokuriku regions were declared as having “likely entered the rainy season.” This followed Monday’s declaration for the Tokai, Kinki, and Chugoku regions.
Q2: What precautions should residents take during the rainy season?
A2: Authorities recommend preparing emergency supplies, confirming multiple evacuation routes that avoid flood-prone areas, and clearing gutters and drains of debris. Residents should remain alert for landslides, river overflows, and flooding in low-lying areas.
Source:https://www.japantimes.co.jp/news/2025/06/10/japan/japan-rainy-season/
