Tropical Cyclones in 2020 > Report on Typhoon Higos (2007): 17 to 19 August 2020

3.3 Typhoon Higos (2007): 17 to 19 August 2020

Higos was the third tropical cyclone affecting Hong Kong in 2020. The Increasing Gale or Storm Signal, No. 9 was issued during the passage of Higos, the first time since Super Typhoon Mangkhut hitting Hong Kong in 2018.

Higos formed as a tropical depression over the northeastern part of the South China Sea at about 650 km east-southeast of Hong Kong on the night of 17 August. It generally moved northwestwards across the northern part of the South China Sea. While edging towards the vicinity of the Pearl River Estuary, Higos intensified rapidly the next day and developed into a severe tropical storm in the afternoon. Higos further intensified into a typhoon near the Pearl River Estuary that night, reaching its peak intensity in the small hours of 19 August with an estimated maximum sustained wind of 130 km/h near its centre. It made landfall over Zhuhai on the morning of 19 August. Higos then moved into the western part of Guangdong and weakened gradually during the day. It degenerated into an area of low pressure over Guangxi that night.

According to press reports, 15 persons were injured in Macao during the passage of Higos. There were flooding in low lying areas in Inner Harbour.

The Standby Signal No. 1 was issued at 3:40 a.m. on 18 August when Higos was about 490 km east-southeast of Hong Kong. Local winds were moderate northeasterlies in the morning. With Higos edging closer to the coast of Guangdong, the Strong Wind Signal No. 3 was issued at 2:20 p.m. on that day when Higos was about 250 km southeast of Hong Kong. Locally, winds became generally fresh to strong east to northeasterlies in the evening. As Higos adopted a track closer to Hong Kong and continued to intensify, the No. 8 Northeast Gale or Storm Signal was issued at 10:40 p.m. on 18 August when Higos was about 100 km south of the Hong Kong Observatory. Local winds strengthened rapidly around midnight with strong to gale easterlies generally affecting Hong Kong. As winds over Hong Kong were expected to increase significantly when Higos skirted past to the southwest of Hong Kong closely, the Increasing Gale or Storm Signal No. 9 was issued at 1:30 a.m. on 19 August when Higos was about 90 km south of the Hong Kong Observatory. Up to gale force east to southeasterly winds affected many places in Hong Kong in the early morning on 19 August, with winds reaching storm force offshore and hurricane force on some of the high ground. Higos came closest to Hong Kong around 5 a.m. on 19 August with its centre passing about 80 km west-southwest of the Hong Kong Observatory. Higos made landfall over Zhuhai in the morning while local winds subsided. The No. 8 Southeast Gale or Storm Signal was issued at 7:40 a.m. to replace the Increasing Gale or Storm Signal No. 9. As Higos continued to weaken and depart from Hong Kong, the Strong Wind Signal No. 3 was issued at 11:10 a.m. and all tropical cyclone warning signals were cancelled at 1:20 p.m. that day.

Under the influence of Higos, maximum hourly mean winds of 98, 98 and 82 km/h and maximum gusts of 158, 129 and 112 km/h were recorded at Tai Mo Shan, Cheung Chau and Waglan Island respectively. A maximum sea level (above chart datum) of 3.38 m and a maximum storm surge (above astronomical tide) of 1.02 m were recorded at Tsim Bei Tsui. The lowest instantaneous mean sea-level pressures recorded at some selected stations are as follows:

Under the influence of the rain bands associated with Higos, there were heavy squally showers and thunderstorms in Hong Kong on 18 and 19 August. More than 150 millimetres of rainfall were recorded over the territory during this period and the Amber Rainstorm Warning and the Landslip Warning were once issued.

In Hong Kong, at least 7 people were injured during the passage of Higos. There were around 800 reports of fallen trees and 2 reports of flooding. Two campers were stranded in Tap Mun and had to be rescued by police officers. Private cars were damaged by a fallen tree in Shek Mun. Windows were broken in an apartment building in Tseung Kwan O. There were backflow of sea water in Tai O and reports of minor flooding in some areas. 14 flights to the Hong Kong International Airport were diverted.