HONG KONG – The Hong Kong Observatory issued typhoon signal No. 3 at 2:20 pm on Saturday as tropical storm Wipha intensified and moved towards the vicinity of the Pearl River Estuary.

The alert, which means that winds with mean speeds of 41 to 62 kilometers per hour are expected, came 12 hours after the forecaster had issued the standby signal No. 1.

“Make sure objects likely to be blown away are securely fastened or taken indoors. Stay away from the shoreline and do not engage in water sports,” the forecaster said in a 2:20 pm bulletin, warning that seas will be very rough with swells.

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Depending on the distance between Wipha and the Pearl River Estuary, the intensity of the typhoon, and the change in local winds, the observatory will consider issuing the signal No. 8 in the small hours of Sunday, said the forecaster.

Under the influence of storm surge, flooding may occur in low-lying coastal areas Sunday morning, it added.

Kindergarten classes and schools for children with disabilities will be suspended after noon.

At 9 am, Wipha was estimated to be about 640 km east-southeast of Hong Kong and is forecast to move west-northwest at about 25 km per hour across the northeastern part of the South China Sea, edging closer to the coast of Guangdong.

With its outer rainbands and associated strong winds affecting the coastal areas of Guangdong gradually, local winds will strengthen later on Saturday, said the observatory.

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“Wipha will be rather close to the vicinity of the Pearl River Estuary tomorrow (20 July). There will be frequent heavy squally showers and thunderstorms,” reads the HKO bulletin.

The HKO also issued a very hot weather warning at 7:30 am and cautioned the public to beware of heat stroke.