Japan's Meteorological Agency downgraded the emergency rain warning issued in Yamagata Prefecture from the highest level to a warning early on Friday. But officials say the danger is not over yet.

Extremely unstable atmospheric conditions in the Tohoku region triggered the record breaking downpours. Nearly 400 millimeters of rain fell in the prefecture over 24 hours through early Friday.

In the prefectures of Yamagata and Akita, the Nikko, Koyoshi, and Mogami rivers all burst their banks.

Weather officials are still urging people there to exercise maximum caution against flooding and mudslides.

People in the areas covered by the warning need to check surroundings and move to evacuation centers or sturdy buildings.

If they feel it is too dangerous to evacuate from their home, moving to higher floors and staying in rooms facing away from mountain slopes is recommended.