Hong Kong emergency crews worked around the clock with robotic “water-pumping dragons” to clear widespread flooding in the northern New Territories after intense downpours triggered a brief red rainstorm warning early Thursday.

The Hong Kong Observatory issued the red rainstorm signal at 2.40am as intense showers battered the city, following an amber warning that had been in force since 9pm on Wednesday and a flooding alert for the northern New Territories.

It said heavy showers and squally thunderstorms associated with upper-air disturbances were persistently affecting the vicinity of the Pearl River Estuary.

More than 50mm of rain fell across many areas in the morning, exceeding 100mm in Tsuen Wan, Kwai Tsing, Tai Po and Sai Kung, the forecaster said.

“With the upper-air disturbances departing from the coastal areas, showers will ease off and the weather will improve [on Friday],” the forecaster said.

Videos and pictures circulating on social media platform Threads show a KMB double-decker ploughing through severe flooding along Ping Che Road in Fanling.