The Hong Kong Observatory said it will consider issuing the typhoon signal 3 between Friday and Saturday as Tropical Cyclone Trami gradually moves towards the central and northern parts of the South China Sea.

The HKO said in a weather bulletin that it will raise the Standby Signal, No. 1 between 10 pm Thursday and 4 am Friday when Trami is expected to come within 800 kilometers of the city.

“Depending on the movement of Trami and the change in local wind conditions, the observatory will assess the need for issuing the Strong Wind Signal, No. 3 on Friday later and at first on Saturday,” the HKO said.

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It said Trami is expected to move towards the vicinity of Hainan Island gradually. At 4 pm, Trami was centered about 300 kilometers north-northwest of Manila and was forecast to move west at about 10 kilometers per hour across Luzon.

“There are uncertainties in the subsequent movement of Trami,” the observatory said. “It may linger in the vicinity of Hainan Island or even move eastwards across the central and northern parts of the South China Sea again early next week but will weaken gradually.”

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The HKO said weather in Hong Kong on Friday will be fine and dry at first before becoming cloudy with one or two showers later, and there will be swells.