Bangkok heat index hits 52°C as Thailand warns tourists of extreme danger

Bangkok’s heat index stays in the danger zone

Bangkok’s heat index hit the danger range of 42.0-51.9°C multiple times in April and climbed above 52°C on May 4, according to the Bangkok Metropolitan Administration’s Environment Department. The city classifies 52°C+ as extreme danger, when officials say outdoor activity should stop.

The Thai Meteorological Department also reported extreme heat in northern provinces, including Chiang Mai, in early May. By mid-May, Bangkok had cooled to around 35°C and no new extreme heat-index alert was posted on the department’s site.

Who faces the biggest risk

The warnings cover everyone, but they matter most for children under 5, seniors over 60, pregnant women, people with health conditions and outdoor workers. The BMA also singled out tourists, while expats and digital nomads can face extra strain from midday travel, non-AC workspaces and higher cooling costs.

Bangkok said the danger zone lasted for at least 18 straight days by late April. That makes it one of the more punishing stretches of the season for anyone spending long hours outside.

What to do now

BMA advice is simple: avoid outdoor activity between 11 a.m. and 3 p.m., drink water and watch for dizziness, nausea or confusion. In extreme danger, the guidance is to stay indoors.

Anyone with heatstroke symptoms should get medical help right away or call 1669. Bangkok also lists more than 300 air-conditioned Heat Escape Rooms through public buildings and parks, with locations available on the AIR BKK app and other city channels. Read our full Thailand guide for the complete picture.