First black rainstorm warning in three years in Macau, causes floods

Macau experienced its first black rainstorm warning in three years on Saturday as heavy downpours caused widespread flooding in various areas of the city.

The warning, issued by the Meteorological and Geophysical Bureau (SMG), urged residents to take precautionary measures as torrential rains lashed the region. This comes just days after Macau was hit by its first hailstorm in over a decade.

The black rainstorm warning, the highest tier in the city’s weather alert system, was raised at 11:37 a.m. Saturday after earlier yellow and red warnings as intense rainfall pounded the Macau peninsula.

Meteorologists said a low-pressure trough was responsible for the unstable weather, which also included strong winds and lightning.

According to the SMG, Macau’s northern district saw the heaviest rain, with nearly 80mm of rainfall recorded in one hour.

The rainfall was highly concentrated in the Macau peninsula, with the weather station at Sun Yat Sen Memorial Park recording 76.2mm in an hour. In contrast, the Cotai district only saw 24.8mm of rain during the same period.

“Heavy rain generally has three characteristics: short-term, localized and highly random,” the SMG said, noting the challenge of providing accurate, quantitative forecasts for such weather events in the compact territory.

The heavy rain led to the suspension of afternoon classes for all non-tertiary education institutions, while several major roads and the underground tunnel at the Border Gate checkpoint were temporarily closed due to flooding.

Videos on social media showed water gushing into the immigration hall at the Border Gate, forcing authorities to divert passengers to manual channels.

“The rain is intense. In Zhuhai, the water was up to my waist,” one resident told reporters after being forced to turn back from trying to cross the border, as cited in local media reports.

“It’s useless to use an umbrella. Suddenly it rained a lot,” he added.

The downpours also caused significant disruption in the neighboring city of Zhuhai, where a red rainstorm warning was issued, and classes were suspended.

According to Xinhua, three areas in Zhuhai, have issued red alerts for rainstorms, which is the highest level in China’s weather warning system.

Zhuhai has experienced heavy rainfall, with 24-hour precipitation exceeding 250mm at eight stations, five of which have surpassed 300mm, as of 1 p.m. Saturday, according to the city’s meteorological bureau.

In Doumen District, one-hour rainfall had exceeded 100mm by 8 a.m., while two other locations in the city – Xiangzhou District and the Zhuhai National Hi-tech Industrial Development Zone – have also issued red alerts for rainstorms. The extreme weather led Zhuhai authorities to suspend all shuttle buses at the city’s bus and tourist terminals, while passenger ferries from Xiangzhou Pier and Hengqin Pier to the estuary islands were also temporarily halted.

“The entry lane had to be temporarily closed and some passing vehicles had to turn back temporarily,” the report stated, noting the accumulation of water on the roads had affected customs clearance at the Gongbei Port.

The bus terminal at the Border Gate also saw water coming down from the ceiling.

Meanwhile, despite the harsh weather, some drivers were spotted trying to cross the Hong Kong-Zhuhai-Macao bridge, though authorities urged the public to avoid peak hours.

The black rainstorm warning in Macau was downgraded to a yellow warning at 12:15 p.m. as the rain eased, but the city’s weather bureau warned unstable conditions could persist until yesterday, with the possibility of more thunderstorms.

Yet yesterday was the first time in over two weeks that the sun shone.

The intense rainfall came just days after Macau experienced its first hailstorm in more than a decade.

Last Tuesday, a hailstorm hit the city for the first time since 2011, with social media posts showing ice pellets raining on the city – thefirst to be recorded since 2011 according to the SMG.

Hailstorms are extremely rare in Macau, with the SMG noting that there were only four recorded cases of hail between 1952 and 2011 before this week’s event.

Also in Hong Kong Saturday, the region also experienced a tumultuous weather journey as the observatory initially cautioned about a potential black rainstorm alert.

However, after a few hours, the forecaster downgraded the red warning to amber as thunderstorms and flooding caused hikers to be stranded, schools to suspend classes, traffic to be disrupted and businesses to close. Staff Reporter