Japan is facing a severe heatwave, prompting authorities to issue heatstroke alerts for 26 out of 47 prefectures and set up 'cooling shelters' for residents. Temperatures have reached up to 40°C, setting record highs and causing significant health risks, particularly for the elderly and children. The Japan Meteorological Agency has advised people to stay indoors, use air conditioners, and stay hydrated. The Japanese Association for Acute Medicine plans to introduce a 'most severe' category to the heatstroke index due to increasing fatalities, which have risen to around 1,500 deaths annually. Over the past week, at least four people have died and thousands have been hospitalized due to heatstroke. The government is also working to ensure stable electricity supply to meet the increased demand for cooling.