Tropical Storm Ma-on moved over the South China Sea southeast of Hong Kong on Wednesday morning. At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Ma-on was located at latitude 20.0°N and longitude 116.1°E which put it about 245 miles (395 km) southeast of Hong Kong. Ma-on was moving toward the west-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h). The minimum surface pressure was 984 mb.

Tropical Storm Ma-on maintained its intensity as it moved over the South China Sea southeast of Hong Kong on Wednesday morning. The inner end of a rainband wrapped around the southern and eastern sides of the center of Ma-on’s circulation. However, the distribution of thunderstorms in the rest of Tropical Storm Ma-on was asymmetrical. The strongest thunderstorms were occurring in bands in the southern and western parts of Ma-on. Bands in the eastern and northern parts of the circulation consisted primarily of showers and lower clouds. An upper level ridge over China was producing east-northeasterly winds that were blowing toward the top of Tropical Storm Ma-on. Those winds were causing moderate vertical wind shear and the wind shear was causing the asymmetrical distribution of thunderstorms.

Tropical Storm Ma-on will move through an environment somewhat favorable for intensification during the next 24 hours. Ma-on will move over water where the Sea Surface Temperatures are 29˚C. The upper level ridge over China will continue to cause vertical wind shear. If the vertical wind shear does not increase, then Tropical Storm Ma-on could strengthen during the next 24 hours. There is a chance Ma-on could strengthen to a typhoon.

Tropical Storm Ma-on will move around the southwestern part of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Ma-on toward the west-northwest during the next 36 hours. On its anticipated track Tropical Storm Ma-on could be south of Hong Kong in 12 hours. The center of Ma-on could make landfall on the south coast of China near Yangjiang and Dianbai in 24 hours. Tropical Storm Ma-on will bring gusty winds and locally heavy rain to southern China. Heavy rain could cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Typhoon Tokage was passing east of Japan. At 5:00 a.m. EDT on Wednesday the center of Typhoon Tokage was located at latitude 35.8°N and longitude 149.4°E which put it about 475 miles (770 km) east of Tokyo, Japan. Tokage was moving toward the north-northeast at 13 m.p.h. (20 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 961 mb.