Tropical Storm Dujuan developed east of Mindanao on Thursday. At 10:00 a.m. EST on Thursday the center of Tropical Cyclone Dujuan was located at latitude 7.3°N and longitude 131.6°E which put it about 430 miles (695 km) east of Davao, Philippines. Dujuan was moving toward the west-northwest at 4 m.p.h. (6 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.
The circulation around an area of low pressure east of the Philippines strengthened on Thursday morning and the Japan Meteorological Agency designated the system as Tropical Storm Dujuan. The distribution of thunderstorms around Tropical Storm Dujuan was asymmetrical. The strongest thunderstorms were occurring in bands in the western half of Dujuan. Bands in the eastern half of the tropical storm consisted primarily of showers and lower clouds. Storms west of the center of circulation began to generate upper level divergence which pumped mass away to the west of the tropical storm. Winds to tropical storm force extended out 100 miles (160 km) from the center of Dujuan.
Tropical Storm Dujuan will move through an environment somewhat favorable for intensification during the next 36 hours. Dujuan will move over water where the Sea Surface Temperature is near 29°C. It will move under the southern part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds which will blow toward the top of Tropical Storm Dujuan. Those winds will create moderate vertical wind shear and they are causing the asymmetrical distribution of thunderstorms. The wind shear will inhibit intensification, but it will not be strong enough to prevent Dujuan from strengthening. Tropical Storm Dujuan is likely to intensify gradually during the next 36 hours.
Tropical Storm Dujuan will move south of a high pressure system over the Western North Pacific Ocean. The high will steer Dujuan toward the west-northwest during the next several days. On its anticipated track Tropical Storm Dujuan could approach northeastern Mindano in 48 hours. Dujuan could bring gusty winds and locally heavy rain to Mindano and other parts of the southern Philippines.