Tropical Storm Saola formed over the Western North Pacific Ocean northeast of Luzon during Wednesday night. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Saola was located at latitude 20.5°N and longitude 124.5°E which put it about 250 miles (400 km) northeast of Aparri, Philippines. Saola was moving toward the northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 998 mb.

A small low pressure system northeast of Luzon strengthened during Wednesday night and the Japan Meteorological Agency designated the system as Tropical Storm Saola. The circulation around Saola was small. Winds to tropical storm force extended out 30 miles (50 km) in the southern side of Saola’s circulation. The winds win the northern side of the circulation were blowing at less than tropical storm force.

More thunderstorms were forming near the center of Tropical Storm Saola. Storms near the center began to generate upper level divergence that pumped mass away from the tropical storm. Bands of showers and thunderstorms developed around Tropical Storm Saola. The bands were beginning to revolve around the center of Saola’s circulation.

Tropical Storm Saola will move through an environment mostly favorable for intensification during the next 24 hours. Saola will move over water where the Sea Surface Temperatures are near 30°C. It will move under the southern part of an upper level ridge over South Asia and Southeast Asia. The ridge will produce easterly winds that will blow toward the top of Saola’s circulation. Those winds will cause some vertical wind shear and the wind shear will inhibit intensification. The vertical wind shear will probably not be enough to prevent intensification and Tropical Storm Saola is likely to intensify during the next 24 hours.

Tropical Storm Saola will move around the southwestern part of a high pressure system over the Western North Pacific during the next 12 hours. The high pressure system will steer Saola toward the northwest during that time period. A large counterclockwise monsoon gyre is forecast to develop east of the Philippines. The monsoon gyre will pull Saola back to the south during the next several days. On its anticipated track, Tropical Storm Saola is forecast to make a counterclockwise loop east of Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 08W was east of the Marianas. At 5:00 a.m. EDT on Thursday the center of Tropical Depression 08W was located at latitude 16.5°N and longitude 149.2°E which put it about 225 miles (365 km) east of Anatahan. Tropical Depression 08W was moving toward the west at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1000 mb. Tropical Depression 08W is forecast to slowly strengthen.