Forecaster also warns of unstable weather from Sunday as low-pressure area near the Philippines may develop into tropical cyclone

The Hong Kong Observatory has said it may issue the typhoon standby signal No 1 on Friday night at the earliest, as the forecaster warned of unstable weather from Sunday onwards.

An area of low pressure near Luzon, which is currently about 800km (497 miles) away from Hong Kong, is expected to develop into a tropical cyclone between Friday night and Saturday morning, according to the Observatory.

“The Observatory will consider issuing the standby signal No 1 by then,” it said.

Under the influence of an anticyclone aloft, the weather would still be mainly fine in the city on Saturday, before it deteriorates from the next day when winds were expected to strengthen gradually, it added.