An unusually warm winter in 2019/20 in central China and Japan was followed by a summer that saw record-breaking rainfall in the region, triggering severe flooding and landslides. A research team from the University of Tsukuba has now examined the conditions giving rise to these extreme weather events, identifying warm sea surface temperature conditions in the Indian Ocean as a common factor in both events. This finding will be useful in the future prediction of extreme weather patterns in East Asia.