Last week, MetMalaysia issued a Level 1 advisory after six areas in Peninsular Malaysia experienced maximum daily temperatures of between 35 and 37 degrees for three consecutive days.
The alert by the meteorological department came amid the southwest monsoon season, which began in May and is set to persist till mid-September, bringing hot and dry weather and reduced rainfall across most regions.
Health experts warned that the country’s current heat warning system remained inadequate, according to a report in The Star newspaper, as it overlooked the wet-bulb temperature (WBT), a key metric that assesses the threat faced by humans based on heat and humidity levels.
WBT measures the lowest temperature air can reach through evaporative cooling, like sweat evaporating from skin. The higher the WBT is, the more risk humans face.
Sustained temperatures between 31 and about 35 degrees, along with humidity levels above 90 per cent, are known to cause high WBT readings in a specific area, the experts said.
“When the air is very humid, sweat doesn’t evaporate efficiently,” Victor Hoe, a public health specialist at Universiti Malaya said. “This reduces our body’s ability to cool down, leading to overheating, which can be dangerous or even deadly,” he added.
