Singapore is experiencing its third monsoon surge of the year, with heavy downpours forecast until 21 March. While this will bring temporary relief from the recent heat – with temperatures potentially dipping to around 22°C – they are expected to rise again, ranging between 24°C and 34°C for the rest of March.

Despite the rains, no significant flooding has been reported, but authorities remain cautious and have issued flood risk alerts in vulnerable areas. The downpours provide a reprieve from the scorching first half of March, which saw temperatures peak at 35.1°C in Newton on 4 March.

A national strategy to combat extreme heat

As Singapore braces for hotter months between March and May, the Mercury Taskforce has unveiled a comprehensive heat response plan. Formed in 2023, this coalition of 37 government agencies, including the Ministry of Health and the Ministry of Social and Family Development, has developed measures to protect residents from heat stress.

A network of cooling spaces will be set up across the island, including community centres, Residents’ Networks, and indoor sports halls. These air-conditioned zones will provide relief during periods of extreme heat, particularly for vulnerable groups such as the elderly, young children, and manual labourers.

In addition to communal cooling spaces, individuals are encouraged to create their own “cool zones” at home by avoiding heat-emitting appliances and ensuring proper ventilation. Simple practices such as cool showers, wet towels, and cold water misting are recommended for relief.

Monitoring heat stress with precision

To ensure timely and accurate responses, Singapore employs the Wet Bulb Globe Temperature (WBGT) index to measure heat stress. This globally recognised system factors in air temperature, humidity, wind speed, and solar radiation. A WBGT reading of 33°C or higher signals high heat stress, prompting precautionary measures.

Recognising the importance of real-time data, the government plans to expand the network of WBGT monitoring stations from the current nine to 17 by mid-2025. Locations like Jurong Island and Punggol Waterway will be equipped with these sensors to ensure more comprehensive coverage.

Protecting vulnerable populations

Labour-intensive sectors, especially construction, are particularly susceptible to heat stress. Existing regulations mandate that workers engaged in physically demanding tasks receive at least 15 minutes of rest under shade every hour during extreme heat. The Mercury Taskforce’s guidelines will reinforce these measures, ensuring the health and safety of outdoor workers.

Schools, too, will adopt protective measures. During heatwaves, preschools will suspend outdoor activities between 11 am and 4 pm — the period of peak heat stress. Similarly, primary and secondary schools will implement “dress-down” policies, allowing students to wear breathable, moisture-wicking clothing.

If heat conditions worsen, the Ministry of Education may shift schools to partial or full home-based learning to minimise exposure.

Defining and responding to heatwaves

In Singapore, a heatwave is officially declared when temperatures reach at least 35°C for three consecutive days, with the mean daily temperature at or above 29°C. Should such conditions arise, a joint media advisory will be issued, urging the public to take preventive measures. The advisory will remain in effect until the Meteorological Service Singapore (MSS) determines that temperatures have stabilised.

Given the unpredictability of tropical weather, authorities caution that heatwave forecasts may not be available far in advance. However, in instances where conditions align, advisories will be issued as early as possible.

While heatwaves are a concern, Singapore’s current La Niña conditions are expected to moderate temperatures, reducing the likelihood of a heatwave in 2025. La Niña typically brings cooler and wetter weather, contrasting the hotter and drier patterns of El Niño, which have historically been linked to all six of Singapore’s past heatwaves.

Learning from the past and preparing for the future

The urgency of a unified heat response is underscored by data from The Lancet, which reported between 71 and 124 hospital admissions for heat-related illnesses annually in Singapore from 2010 to 2020.

The Mercury Taskforce’s proactive approach, from setting up cooling stations to issuing timely alerts, reflects Singapore’s commitment to resilience in the face of rising temperatures.

While La Niña offers a temporary reprieve, the long-term challenge of climate change demands sustained vigilance and adaptation.

In a nation where scorching days are becoming the norm, Singapore’s heatwave response plan serves as a vital lifeline to ensure that when the mercury soars, no one is left to weather the storm alone.