Authorities confirm four cases of flooding so far, with affected locations including Tuen Mun Road and Northwest Tsing Yi Interchange

The Hong Kong Observatory has issued an amber rainstorm warning, less than an hour after downgrading its second black signal of the year to red, even as some parts of the city grappled with the effects of flash flooding.

The amber rainstorm warning was issued at 12.30am on Saturday, just 45 minutes after the local forecaster sent out a red signal.

Saturday morning saw the city issue its second black rainstorm signal of the year, with the first such warning going out on Tuesday.

“Please continue to exercise due care. People who have to travel should carefully consider weather and road conditions and take necessary precautions,” the Observatory said as it issued the amber warning.