The Baiu front stagnated near Japan’s main island of Honshu in early June, and a series of stationary linear mesoscale convective systems hit the Pacific side of eastern and western Japan. Such conditions brought unprecedented 24-hour June rainfall at 167 stations. Record-high temperatures were observed in northern/eastern Japan and elsewhere from mid-July onward. The average temperature for northern Japan in late July was the highest for the region since records began in 1946, and that for eastern Japan was the second highest for the region. The average temperature for the Sea of Japan side of eastern and western Japan in early August was also the highest ever.
Source: World Meteorological Organization