
The Environment Department and the Thai Meteorological Department have reported that Bangkok's heat index has reached the "Danger" level, peaking at 51.9°C.
Authorities warned residents of the high "feels like" temperature and the associated risk of heatstroke, advising the public to reduce outdoor activities between 11am and 3pm.
The government has also identified eight vulnerable groups requiring urgent monitoring and opened "Bangkok heat escape rooms" across the city.
The departments explained that the heat index represents the "feels like" temperature the body experiences, rather than the general air temperature.
This figure is calculated by combining air temperature with relative humidity.
Higher humidity reduces the body's ability to perspire, increasing perceived heat and the risk of heat-related illnesses.
An updated weather report for Thursday (June 25, 2026) indicated that Bangkok has entered the red zone.
The government categorised the heat index into four severity levels with corresponding recommendations:
Excessive heat can affect health directly and indirectly.
Early symptoms include fatigue, dizziness, rashes, red and swollen skin, and cramps, which can escalate to fatal heatstroke if left unattended.
Authorities identified eight vulnerable groups requiring special care:
The public can monitor the situation and access assistance through the following channels: