Heavy rain lashed the cities of Yangjiang, Zhanjiang and Maoming in China’s southern province Guangdong after the storm system made landfall on Sunday evening.

On Sunday it brushed past Hong Kong, where it felled trees and scaffolding, grounded flights and sent nearly 280 people into shelters.

China’s national forecaster said it had weakened to a tropical storm upon landfall and forecast it to skirt the coast of Guangdong and move southwesterly towards Vietnam.

Heavy rain is forecast for mainland Chinese coastal regions such as Guangdong, Guangxi, Hainan and Fujian until Tuesday morning, with warnings of flash floods, landslides and wind hazards.

The system will move into the Gulf of Tonkin late Monday morning, over which it will gather intensity before hitting Vietnam’s northern coast on Tuesday, the forecaster said.