Tropical Cyclone Dolphin: Hong Kong sees hottest day on record as Observatory HQ records 36.9°C

Hong Kong experienced its hottest day on record on Sunday, August 9, 2026, with temperatures reaching an unprecedented 36.9 degrees Celsius at the Observatory headquarters, according to the Hong Kong Observatory (HKO). The heatwave, influenced by Tropical Cyclone Dolphin, persisted throughout the day and into the night, with temperatures exceeding 38 degrees Celsius in other parts of the city.

The HKO warned that the extreme heat would continue into Tuesday, with the potential for temperatures to rise even higher midweek. A rain system was expected to bring relief by Wednesday as upper-air disturbances passed through the region. The HKO highlighted that the city may face record-breaking high temperatures in the coming years due to climate change and the anticipated "super-strong" El Niño event.

El Niño, characterized by abnormally warm sea surface temperatures in the equatorial Pacific, occurs naturally and contributes to global warming when combined with human-induced climate change. The past month in Hong Kong marked the second-rainiest July on record, with numerous rainstorm warnings issued. The Intergovernmental Panel on Climate Change has reported a consistent increase in the intensity and frequency of heatwaves since the 1950s, attributed to human-caused climate change.

Hong Kong's average temperature has risen by 1.7 degrees Celsius since the Industrial Revolution, according to research from the NGO Berkeley Earth. As greenhouse gas concentrations continue to grow, heatwaves are projected to become longer and more lethal, posing significant risks to public health, especially in regions where prolonged exposure to extreme heat and humidity becomes inevitable.