Scorching heat with high humidity is expected to continue for much of Japan on Tuesday.
The Meteorological Agency and the Environment Ministry have issued heatstroke alerts in parts of eastern, western and southwestern Japan.
Weather officials say Pacific coastal areas from Kanto to the west will see sunshine drive up temperatures. These areas are away from a seasonal rain front, which is now stationary near northern Japan.
Daytime highs are expected to reach 37 degrees Celsius in Owase City in Mie Prefecture; 36 degrees in central Tokyo, Shizuoka City and Miyazaki City; and 35 degrees in Fukuoka City.
A number of people have died with symptoms of heatstroke over the past several days.
People are urged to avoid going outdoors if possible, use air conditioners appropriately, drink water and replenish salt from time to time.
Families are also advised to pay special attention to the elderly and children who are vulnerable to heatstroke.