Tropical Storm Tapah developed east of Taiwan on Thursday.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Tapah was located at latitude 23.3°N and longitude 126.5°E which put it about 150 miles (245 km) east-southeast of Ishigaki, Japan.  Tapah was moving toward the west at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 965 mb.

A distinct low level center of circulation formed on the northern side of an area of thunderstorms east of Taiwan on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Tapah.  The distribution of thunderstorms around Tapah was asymmetrical.  Most of the thunderstorms  were occurring in bands in the southern half of the circulation.  Bands in the northern half of the tropical storm consisted primarily of showers and lower clouds.  Storm on the southern side of the center began to generate upper level divergence which pumped mass away from the tropical storm.  The circulation around Tropical Storm Tapah was very large.  Winds to tropical storm force extended out about 250 miles (400 km) from the center of circulation.

Tropical Storm Tapah will move through an environment favorable for intensification during the next several days.  Tapah will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Some drier air north of Tropical Storm Tapah could inhibit the development of bands of thunderstorms on the northern side of the circulation.  Tropical Storm Tapah is likely to intensify and it could strengthen into a typhoon during the weekend.

Tropical Storm Tapah will move around the western end of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Tapah more toward the northwest on Friday.  Tapah will move more toward the north when it rounds the western end of the ridge.  On its anticipated track Tropical Storm Tapah could move over the southern Ryukyu Islands in about 12 hours.  The center of Tapah could pass west of Okinawa in about 24 hours.