Japan's weather officials say unstable conditions will likely bring heavy rain to western Japan from Monday through Wednesday.

The Meteorological Agency says atmospheric conditions will become unstable due to warm, moist air which is flowing into a low-pressure system and a rain front stretching over the East China Sea.

Localized downpours of more than 50 millimeters per hour and thunder are expected in western Japan from Monday through Wednesday.

In the 24 hours through Tuesday morning, up to 250 millimeters of rain is expected in southern parts of the Kyushu region, up to 200 millimeters in northern Kyushu, and up to 80 millimeters in the Chugoku and Shikoku regions.

Weather officials forecast that the rain front and low-pressure system will move eastward, bringing unstable atmospheric conditions and possible heavy rain to eastern Japan on Tuesday and Wednesday and to northern Japan on Wednesday.

They are calling on people to be on the alert for landslides, flooding in low-lying areas and swollen rivers, as well as lightning strikes, sudden gusts of wind, and hailstorms.