Tropical Cyclones in 2019 > Report on Tropical Depression Kajiki (1914): 1 – 4 September 2019

3.5 Tropical Depression Kajiki (1914): 1 – 4 September 2019

Kajiki was the fifth tropical cyclone necessitating the issuance of tropical cyclone warning signal by the Hong Kong Observatory in 2019.

Kajiki formed as a tropical depression over the northern part of the South China Sea at about 480 km southeast of Hong Kong on the morning of 1 September and moved westwards across the northern part of the South China Sea. Kajiki intensified slightly during the day with an estimated maximum sustained wind reaching 55 km/h near its centre. It turned to track southwestwards after moving across the southeastern part of Hainan Island on the morning of 2 September. Kajiki made landfall over the coast of central Vietnam and lingered over the region on 3 September. It finally degenerated into an area of low pressure over the coastal waters of central Vietnam the next day.

After the formation of Kajiki on the morning of 1 September, the Hong Kong Observatory issued the Standby Signal No. 1 at 8:40 a.m. when Kajiki was centred about 470 km southeast of the territory. Local winds during the day were moderate to fresh northeasterlies and occasionally reached strong force offshore and on high ground. With Kajiki edging closer to the territory, the Strong Wind Signal No. 3 was issued at 4:20 p.m. that afternoon when it was about 340 km south-southeast of Hong Kong. Local winds were in general fresh to strong easterlies at night. Kajiki was closest to Hong Kong at around 9 p.m. that night, skirting past about 330 km south of the territory. As Kajiki made landfall over the southeastern coast of Hainan Island and moved away from Hong Kong, the Standby Signal No. 1 was issued to replace the Strong Wind Signal No. 3 at 10:40 a.m. on 2 September. Under the combined effect of Kajiki and continental anticyclone, local winds remained occasionally strong offshore and on high ground. As winds over Hong Kong weakened, all tropical cyclone warning signals were cancelled at 9:20 a.m. on 3 September.

Under the influence of Kajiki, a maximum sea level (above chart datum) of 3.0 m was recorded at Tsim Bei Tsui and a maximum storm surge of 0.39 m (above astronomical tide) was recorded at Tai Miu Wan. At the Observatory Headquarters, the lowest instantaneous mean sea-level pressure of 1004.5 hPa was recorded at 3:23 p.m. on 1 September.

Affected by the rainbands associated with Kajiki, there were occasional heavy squally showers and thunderstorms on 1-3 September. The showers were particularly heavy around noon on 2 September, which necessitated the issuance of the Amber Rainstorm Warning Signal. More than 50 millimetres of rainfall were generally recorded over the territory during these three days, and rainfall even exceeded 150 millimetres in Sai Kung, Sha Tin and Tai Po.

Kajiki did not cause any significant damage in Hong Kong. According to press reports, Kajiki left at least six deaths and ten missing in Vietnam during its passage.