Rain pouring onto Hong Kong and southern China overnight flooded city streets and some subway stations, halting transportation and forcing schools to close Friday.
Videos circulating on social media show flooded streets in Hong Kong and nearby Guangdong province, with vehicles driving through the water and rescue teams using rafts to navigate the streets.
Water rushed down the stairs and escalators of a flooded underground subway station in Hong Kong, and cars were caught in muddy water on flooded streets, including in the cross-harbor tunnel that connects Hong Kong Island with Kowloon.
The heavy downpours led Hong Kong and the mainland city of Shenzhen to close schools, and non-essential workers in Hong Kong were urged to not head to their workplaces Friday.
Most bus services in Hong Kong were halted.
The Hong Kong Observatory said it recorded 158.1 millimeters (6.2 inches) of rain in the hour between 11 pm Thursday and midnight, the highest recording since records began in 1884. More than 200 millimeters (7.8 inches) fell in Kowloon and Hong Kong Island.
On the mainland, more than 11,000 people were evacuated from water-logged areas in Meizhou, a city in Guangdong province, according to state broadcaster CCTV. Trains and flights were suspended in Guangdong and several landslides blocked roads the report said.
Shenzhen's total rainfall was 469 millimeters (18.4 inches) the heaviest rainfall since Shenzhen started meteorological records in 1952, CCTV said.
Beijing issued a flood disaster warning for several districts of the Chinese capital, forecasting heavy rainfall through Saturday night.
The Hong Kong stock exchange did not open Friday as authorities warned that the extreme weather would continue until evening.
The city observatory attributed Friday's rain to a trough of low pressure associated with the remnants of a recent typhoon.