Atmospheric conditions remain unstable from western to northern Japan as warm and moist air continues to flow into a front stretching across the archipelago.

The conditions are expected to continue until Sunday, bringing heavy rain to many parts of the country. Weather officials are advising people to stay up to date with the latest information and evacuate before they face imminent danger.

The northeastern prefecture of Miyagi saw record rainfall overnight through Saturday morning due to the front and a low pressure system.

In the hour to 8:00 a.m. on Saturday, Osaki City in Miyagi had a downpour of 28 millimeters.

Weather officials say the extreme conditions have heightened the risk of landslides and flooding of rivers.

They warn that localized downpours of 50 millimeters or more per hour, accompanied by thunder, could hit western Japan on Saturday and eastern and northern Japan overnight through Sunday.

In the 24 hours through Sunday morning, up to 150 millimeters of rain is forecast in the Kansai and Tokai regions, while up to 120 millimeters is expected in the Tohoku region and the northern prefecture of Hokkaido. Up to 100 millimeters of rain is likely to fall in the southern Kyushu and Kanto-koshin regions, and up to 80 millimeters in the Shikoku, Chugoku and Hokuriku regions.

Weather officials are urging residents in the northeastern region of Tohoku to be prepared for the possibility of landslides, swollen rivers, and flooding in low-lying areas. They say people in western and eastern Japan should also be on alert.