BANGKOK — The heat index in Bangkok on Thursday entered the “extreme danger” zone for the first time this season, with “feels like” temperatures reaching or exceeding 52 degrees Celsius, prompting City Hall to issue an urgent public health warning.

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The Bangkok Metropolitan Administration issued the warning at 7:30 a.m., urging people to avoid outdoor activities during the daytime as the combination of high heat and oppressive humidity pushed the capital into a level of thermal stress rarely seen even in Thailand’s notoriously hot season. People in high-risk groups were told to take extra care of themselves, as prolonged exposure to such conditions can lead to heatstroke, dehydration and potentially fatal organ failure.

The groups most vulnerable include young children aged up to five years old, the elderly aged 60 or older, pregnant women, patients with chronic diseases, individuals with obesity, people who consume alcohol, outdoor workers, those who exercise outdoors and tourists—many of whom may be unaccustomed to the intensity of Bangkok’s heat and may not recognize the warning signs of heat-related illness.

Official maximum temperatures in the capital on Thursday are forecast to range between 35 and 38 degrees Celsius, with a 20 percent chance of thunderstorms in the area, according to the Meteorological Department. Those numbers, while hot, do not fully capture the danger. The heat index factors in both air temperature and relative humidity, which on Thursday pushed the “feels like” temperature into a range that the US National Weather Service classifies as “extreme danger,” where heatstroke is highly likely with prolonged exposure or physical activity.

Since April 1, the city’s heat index had been in the “danger” zone, where the temperature the human body can actually feel ranged between 42 and 51.9 degrees Celsius. The two less harmful levels are “caution” (27 to 32.9 degrees) and “warning” (33 to 41.9 degrees). Thursday’s spike into the “extreme danger” category represents a significant escalation, one that health officials have been bracing for as the region’s summer heat intensifies.

Bangkok on Thursday entered the “extreme danger” zone for the first time this season, with “feels like” temperatures higher than or equal to 52 degrees Celsius, City Hall has warned.

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In response, Bangkok has introduced dozens of cooling centres citywide, including air-conditioned public facilities such as libraries, community centres and select shopping malls where residents and tourists can escape the heat. The BMA has also advised people to stay hydrated, wear light-coloured and loose-fitting clothing, avoid caffeinated and alcoholic beverages which can accelerate dehydration, and to check on elderly neighbours or others who may be living without air conditioning.

For outdoor workers, the warning presents a difficult choice between earning a day’s wage and protecting their health. For tourists, many of whom plan outdoor activities during their holidays, the advice is clear: stay indoors during peak heat hours, typically between 11 a.m. and 3 p.m., and reschedule any non-essential excursions for early morning or after sunset.

The heat index is considered a more suitable way to indicate the risk of heat-related health impacts than using only the maximum temperature, because humidity impairs the body’s ability to cool itself through sweating. When humidity is high, sweat does not evaporate efficiently, and the body’s internal temperature can rise to dangerous levels even when air temperatures are moderate. On Thursday in Bangkok, both temperature and humidity were high, creating a potentially lethal combination.

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As climate change drives more frequent and intense heatwaves globally, Bangkok is increasingly finding itself on the front lines of extreme heat events. Thursday’s “extreme danger” reading may be a sign of things to come, and authorities are scrambling to adapt. For now, the advice is simple: stay cool, stay hydrated and stay indoors. The heat index may drop by evening, but for the next several hours, Bangkok is a city under thermal siege.

-Thailand News (TN)