Hong Kong’s stock market operator canceled its morning trading session on Monday after the city’s weather observatory issued a Black Rainstorm Warning.

The Hong Kong Observatory issued the warning at 8:20 a.m. local time and it has stayed in place since then. That prompted Hong Kong Exchanges and Clearing Ltd. to cancel morning trading of both securities and derivatives markets, including Stock Connect, in accordance with its rules.

If the rainstorm warning is lowered before 11 a.m., the afternoon session will take place as usual from 1 p.m. Trading will not commence Monday if the warning is still in force by midday.

In 2019, a tropical storm shut Hong Kong’s financial markets for the first time in almost two years after the Observatory raised the storm signal to 8, the third highest number on its scale.