Tropical Storm Ewiniar formed near the coast of South China late on Tuesday. At 11:00 p.m. EDT on Monday the center of Tropical Storm Ewiniar was located at latitude 20.9°N and longitude 110.5°E which put it about 50 miles (80 km) southeast of Zhanjiang, China. Ewiniar was moving toward the northwest at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1000 mb.
A distinct low level center of circulation consolidated in a cluster of showers and thunderstorms moving over the South China Sea near Hainan Island on Monday and the Japan Meteorological Agency designated the system as Tropical Storm Ewiniar. Several bands of showers and thunderstorms developed west of the center of circulation. Bands east of the center consisted primarily of showers and low clouds. Winds to tropical storm force were occurring within 60 miles (95 km) of the center o circulation.
Tropical Storm Ewiniar has 12 to 24 hours during which it could intensify if the center remains over water. The Sea Surface Temperature of the water near the coast of South China is about 30°C. Ewiniar is under the southwestern portion of a narrow upper level ridge. The ridge is producing weak southerly winds which are blowing toward the top of the circulation. Those winds will cause some vertical wind shear but the shear will not be strong enough to prevent intensification. Even though the atmospheric and oceanic environments are favorable for intensification, a portion of the circulation of Tropical Storm Ewiniar is already over land. The friction caused by the flow of air over the land will inhibit intensification. Tropical Storm Ewiniar could intensify a little more if the center remains over water.
The upper level ridge was steering Tropical Storm Ewiniar toward the northwest. A general motion toward the north is expected for the next 24 to 48 hours. On its anticipated track the center of Tropical Storm Ewiniar will move near the east coast of the Leizhou Peninsula. Ewiniar could move inland near Wuchuan and Dianbai. Tropical Storm Ewiniar will bring some gust winds to South China, but the greater risks are the potential for heavy rain and floods.
Tropical Storm Khanun intensified into a typhoon southeast of Hong Kong on Saturday. At 11:00 p.m. EDT on Saturday the center of Typhoon Khanun was located at latitude 20.1°N and longitude 114.2°W which put it about 170 miles (275 km) south-southeast of Hong Kong. Khanun was moving toward the west-northwest at 18 m.p.h. (29 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 965 mb.
The circulation of Typhoon Khanun became much more well organized on Saturday. A small circular eye formed at the center of circulation. A tight ring of strong thunderstorms formed around the eye. The strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Khanun. There were many more showers and thunderstorms in the western half of the circulation. The storms in the core of Khanun were generating upper level divergence which was pumping mass away to the west of the typhoon. Winds to typhoon force extended out about 70 miles (110 km) from the center of circulation. Winds to tropical storm force extended out about 250 miles (400 km) from the center.
Typhoon Khanun will move through an environment favorable for intensification for about another 12 to 18 hours. Khanun will move over water where the Sea Surface Temperature is near 29°C. An upper level ridge north of Typhoon Khanun is producing easterly winds which are blowing toward the top of the circulation. The easterly winds are causing some vertical wind shear, but the shear is not strong enough to prevent intensification. The circulation of Typhoon Khanun will interact with land in 12 to 18 hours and that interaction should halt further intensification.
The ridge north of Khanun has been steering the typhoon toward the west-northwest. The ridge is forecast to strengthen on Sunday and it will steer Typhoon Khanun more toward the west. On its anticipated track the center of Typhoon Khanun will pass south of Hong Kong and Macao on Sunday. Khanun will approach the south coast of China near Zhanjiang in 12 to 18 hours. Typhoon Khanun will bring strong gusty winds and locally heavy rain to southern China west of Hong Kong and Macao. The heavy rain could cause flooding in some locations. Typhoon Khanun will be weaker when it moves over the Gulf of Tongking in about 24 hours.