The Hong Kong Observatory said it will issue the typhoon signal No. 1 on Monday morning as Super Typhoon Man-yi, which is expected to weaken gradually, edged closer to the territory.

The HKO said in a weather bulletin that it will raise the Standby Signal, No. 1 tomorrow after the typhoon comes within 800 kilometers of the city around midnight on Sunday.

“The observatory will issue the Standby Signal, No. 1 between 6 am and 9 am tomorrow morning,” the HKO said.

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The observatory said it will consider issuing a higher typhoon warning on Monday night or Tuesday morning depending on the distance between Man-yi and the Pearl River Estuary, changes in its intensity, and local wind conditions.

As of 4 pm Sunday, Man-yi was centered about 180 kilometers north-northeast of Manila and was forecast to move northwest or west-northwest at about 25 kilometers per hour across Luzon.

Under the combined effects of Man-yi and the northeast monsoon, it will be windy over the coast of Guangdong on Tuesday, the observatory said, adding that there will be a spring tide in the next couple of days and sea levels will be particularly high during high tide.

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The HKO also said that there will be occasional rain on Tuesday and Wednesday while temperatures will fall progressively, with the minimum temperature dropping to 18 degrees Celsius or below.