Japan's Meteorological Agency is warning that heavy rain and strong winds may continue until Wednesday morning in some parts of northern and eastern Japan.
The agency says a cold front is causing rain clouds to form over the Tokai and Kanto regions, which encompass Nagoya and Tokyo, respectively.
The agency also says 42 millimeters of rain fell in the hour through 5:30 p.m. in Kamogawa City, Chiba Prefecture, east of Tokyo.
Hourly rainfall of more than 30 millimeters is forecast for eastern Japan through late Monday night and into the early hours of Tuesday morning in northern Japan.
Maximum rainfall over the 24-hour period through late Tuesday afternoon is expected to be 120 millimeters along the Pacific coast of the northernmost main island of Hokkaido, and 80 millimeters on the Sea of Japan coast in the northeastern Tohoku region.
A rapidly developing low-pressure system is also bringing strong winds, mainly to northern Japan.
In Kushiro City, Hokkaido, a maximum instantaneous wind speed of 93 kilometers per hour was observed on late Monday afternoon.
Gusts are likely to continue to blow until Tuesday in Hokkaido and on Tohoku's Pacific coast, and through Wednesday morning along the Japan Sea coast of the northeastern region.
A powerful cold air mass may bring snow in mountainous areas along the Sea of Japan coast as far south as the Chugoku region encompassing Hiroshima on Tuesday afternoon and later.
People in these areas are advised to put winter tires on their vehicles and even prepare tire chains before setting out on a drive.