Heatstroke in Japan

After typhoon No. 8 has passed, summer temperatures above 30 degrees have returned. The ministry of the environment warns against heat stroke using a principle called WBGT: Wet Bulb Globe Temperature. This is an empirical index representing the heat stress to which individuals are exposed.

A paper from the end of 2011 described how different ministries are involved in heatstroke warnings:
The Ministry of the Environment has developed and distributes guidelines to prevent heat-related diseases, with specific recommendations for prevention at the local and regional levels [26]. The Ministry of Health, Labor and Welfare (MOHLW) also promotes preventive action on heat through health education activities and the distribution of health promotion materials. These and other national entities maintain websites on the prevention of heat disorders. Forecasts of Wet Bulb Globe Temperature (WBGT—a widely used heat stress index) and levels of heat disorder risk are provided by the National Institute of Environmental Studies (NIES) throughout the summer via the Internet.

The ministry of the environment has published a possible heat stroke calendar, by using combined temperatures from the cities Tokyo, Nagoya, Osaka, Hiroshima, Fukuoka, Sapporo, Sendai and Kagoshima, with cumulative figures of the past five years in the left most column:

The number of days with high temperatures has been increasing the past years. This calendar also shows why October and May are the months which are considered to have the best seasons.