The Chinese region of Hong Kong, which is hilly and highly populated, has seen the heaviest rainfall in 140 years resulting in widespread flooding.
On Thursday night it experienced the most rainfall in an hour since records began in 1884.
The Hong Kong Observatory recorded 158.1mm (6.2 inches) of rainfall between 11pm on Thursday and midnight.
The weather bureau issued a black rainstorm warning last night – the first in nearly two years – which remains in place until midnight on Friday said that since Thursday night, more than 200mm (7.9 inches) of rain had been recorded on Hong Kong’s main island, Kowloon, and the northeastern part of the city’s New Territories. It urged residents to keep safe.
“Heavy rain will bring flash floods,” it warned. “Residents living in close proximity to rivers should stay alert to weather conditions and should consider evacuation” if their homes are flooded, it added.
John Lee, the territory’s chief executive, said he was deeply worried about the extreme flooding and has instructed all departments to make “all-out efforts” to deal with it.
The weather bureau issued the highest “black” rainstorm warning and said the extreme conditions were expected to continue until at least noon (04:00 GMT) on Friday.
Earlier in the week, Typhoon Haikui left a trail of destruction in Taiwan before crossing the strait and making landfall in China’s Fujian province on Tuesday.
The current severe downpour, according to Hong Kong’s observatory, was caused by a “trough of low pressure associated with [the] remnant of Haikui”.
The previous weekend Southern China was hit by two typhoons in quick succession – Saola and Haikui – although Hong Kong avoided a direct hit.
According to experts, climate change has increased the severity of tropical storms, causing more rain and stronger winds to cause flash floods and coastal damage.