Hong Kong vows to revamp heat stress warning system by month’s end

The Hong Kong government aims to overhaul its heat stress warning system by the end of the month, following criticism from former Observatory chiefs regarding its inadequacy during a record-breaking heatwave in summer 2026. Labour and Welfare Chief Chris Sun stated that the government would examine whether the warning system could be better tailored to Hong Kong's weather, adding that thresholds under the three-tier color-coded warning system could be reviewed.

Sun emphasized the importance of in-depth discussions with relevant experts, particularly from the Observatory, to clearly define how the system will be triggered. The Labour Department and the Observatory plan to complete the revamp within the month. Former Observatory chief Lam Chiu-ying had previously called the mechanism "decorative" for only issuing the lowest alert during record-breaking temperatures.

Commissioner for Labour Sam Hui confirmed that his department would revamp the city's heat warning mechanism, expressing that they had many questions when the Observatory recorded soaring temperatures earlier this month. The city's proprietary Hong Kong Heat Index considers factors such as humidity, wind speed, and solar radiation in addition to air temperature.

A reading of 30 triggers the amber warning, and 32 and 34 for the red and black warnings, respectively. However, neither the red nor black warnings have been triggered since the system's introduction in 2023, as employers are not bound by the index, and work stoppages have never been recommended for red or black alerts.