Special Heat Stroke Alert ・ Heat Stroke Alert

Updated at Feb 17（Mon）17:00

Today［Feb 18］

Today［Feb 18］

Tomorrow［Feb 19］

Tomorrow［Feb 19］

This year's Heat Stroke Alert operation
will start from April 23, 2025.

Heat Stress Index: WBGT

Provision of information on Heat Stress Index (WBGT) will start on Apr 23, 2025.

(Blue) Almost safe	(Sky) Caution	(Yellow) Warning	(Orange) Severe Warning	(Red) Danger
< 21 appropriate water replenishment suggested	21 - 25 water should be replenished often	25 - 28 rests should be provided often	28 - 31 heavy exercise prohibited	≥ 31 exercise prohibited

Note

WBGT index is one of the empirical indices representing the heat stress to which an individual is exposed. (ISO7243)
WBGT varies depending on environmental situation and condition.

Contents

• WBGT Guideline
• All about WBGT
• Heat illness prevention/countermeasures
• Materials
• Terms of Use