Tag Archives: Sanya

Typhoon Kajiki Brings Wind and Rain to Hainan

Typhoon Kajiki brought wind and rain to Hainan on Sunday.  At 5:00 a.m. EDT on Sunday the center of Typhoon Kajiki was located at latitude 17.5°N and longitude 109.8°E which put the center about 50 miles (80 km) south-southeast of Sanya, China.  Kajiki was moving toward the west at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 967 mb.

Typhoon Kajiki rapidly intensified to the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale during Saturday night.  A circular eye with a diameter of 25 miles (40 km) formed at the center of Kajiki’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Typhoon Kajiki.  Storms near the center of Kajiki generated strong upper level divergence that pumped large quantities of mass away from the typhoon.  The removal of large amounts of mass caused the surface pressure to decrease rapidly.

The circulation around Typhoon Kajiki became more symmetrical when it rapidly intensified.  Winds to typhoon force extended out 30 miles (50 km) from the center of Kajiki’s circulation.  Winds to tropical storm force extended out 115 miles (185 km) from the center of Typhoon Kajiki.

The Hurricane Intensity Index (HII) for Typhoon Kajiki is 17.8.  The Hurricane Size Index (HSI) is 11.3 and the Hurricane Wind Intensity Size Index (HWISI) is 29.1.  Typhoon Kajiki is similar in size and intensity to Hurricane Sally when Sally hit South Alabama in 2020.

Typhoon Kajiki will move through an environment that is favorable for intensification during the next 24 hours.  Kajiki will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over China.  The upper level ridge will produce northeasterly winds that will blow toward the top of Kajiki’s circulation.  The winds in the lower levels of the atmosphere will also blow from the northeast.  So, there will be little vertical wind shear.  Typhoon Kajiki will intensify during the next 24 hours as long as the center remains south of Hainan.  Kajiki could strengthen to the equivalent of a major hurricane.

Typhoom Kajiki will move around the southern side of a high pressure system over China.  The high pressure system will steer Kajiki toward the west during the next 24 hours.  On its anticipated track, the center of Typhoon Kajiki will continue to pass south of Hainan during the next 12 hours.  Kajiki will hit the coast of  northern Vietnam in 24 hours.

Typhoon Kajiki will continue bring strong winds and heavy rain to Hainan during the next 12 hours.  Heavy rain is likely to cause flash floods in some locations.

Typhoon Kajiki will also bring strong winds and heavy rain to northern Vietnam.  Heavy rain is likely to cause flash floods there as well.  Typhoon Kajiki could cause a storm surge of up to 10 feet (3 meters) along the coast of northern Vietnam.

Tropical Depression Forms South of Hainan Island

A tropical depression formed just to the south of Hainan Island on Friday night. At 11:00 p.m. EDT on Friday the center of Tropical Depression 05W was located at latitude 18.3°N and longitude 109.5°E which put it about 35 miles (55 km) south of Sanya, China. The depression was moving toward the west at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1000 mb.

Thunderstorms developed closer to the center of a low pressure system south of Hainan Island on Friday night and both the Japan Meteorological Agency and the Joint Typhoon Warning Center designated the system as a tropical depression. The distribution of thunderstorms around Tropical Depression 05W was asymmetrical. The strongest thunderstorms were occurring in bands southwest of the center of the tropical depression. Bands in the other parts of the circulation consisted primarily of showers and lower clouds. An upper level ridge centered over southern China was producing moderate northeasterly winds that were blowing toward the top of the depression. Those winds were causing moderate vertical wind shear and they were also causing the asymmetrical distribution of thunderstorms.

The center of Tropical Depression 05W will move near Hainan Island during the next few hours. The northern half of the circulation around the tropical depression will be over Hainan Island, which will inhibit intensification. Tropical Depression 05W will move into an environment favorable for intensification when it moves west of Hainan Island. The tropical depression will move over an area where the Sea Surface Temperatures are near 30°C. The upper level ridge over southern China will continue to produce moderate vertical wind shear. Even with the moderate wind shear, Tropical Depression 05W is likely to intensify to a tropical storm during the next 24 hours.

Tropical Depression 05W will move around the southern part of a subtropical high pressure system over the Western North Pacific Ocean during the next 36 hours. The high pressure system will steer the tropical depression toward the west-northwest. On its anticipated track the center of Tropical Depression 05W will pass near the southern part of Hainan Island. Since the strongest thunderstorms are in the southwestern part of the circulation, the tropical depression will cause mainly gustier winds over Hainan Island. Tropical Depression 05W could approach northern Vietnam in 24 hours. It could bring gusty winds and locally heavy rain to parts of northern Vietnam. Heavy rain could cause flash floods in some locations.