Parts of Japan have been deluged by their heaviest daily rains since records began, officials said Saturday, with reports of more than 100 landslides after a tropical storm.

Mobara city in Chiba prefecture, which borders the capital Tokyo, recorded 392 millimetres of rain overnight into Saturday -- the largest amount to hit the city in a 24-hour span since the Japan Meteorological Agency began the survey in 1976.

The deluge comes at the end of a rain-sodden week for East Asia, after southern Chinese cities were hit by record-breaking downpours that inundated major cities, and Typhoon Haikui toppled trees and caused flooding in Taiwan.

Deadly rains have also hit southern Europe.

Scientists say climate change is intensifying the risk of heavy rain globally, because a warmer atmosphere holds more water.

On Friday, tropical storm Yun-yeung disrupted some railway services and left thousands of households without power in Chiba, Ibaraki and Fukushima regions.

In Mobara, "a river near the city hall flooded on Friday and a car that was running nearby had to be rescued", a city spokesman told AFP.

"The water was overflowing to about waist height," he said, adding that levels had mostly receded by the morning.

He said officials "haven't been able to grasp the full extent of damage".

Two other areas saw around 280 millimetres in 24 hours, according to the weather agency.

There were more than 100 landslides in the region due to heavy rain, public broadcaster NHK reported.

A Chiba prefectural official told AFP that the government flew two helicopters on Saturday to examine damaged areas.