Tropical Storm Phanfone formed east of Palau on Saturday night. At 7:00 p.m. EST on Saturday the center of Tropical Storm Phanfone was located at latitude 8.2°N and longitude 138.3°E which put it about 310 miles (500 km) east of Koror, Palau. Phanfone was moving toward the west-northwest at 14 m.p.h. (22 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 center of circulation in an area of low pressure east of Palau became more well defined on Saturday night and the Japan Meteorological Agency designated the system as Tropical Storm Phanfone. The circulation around Phanfone was still organizing and the distribution of thunderstorms was asymmetrical. Many of the thunderstorms were occurring in bands in the northwestern part of the tropical storm. Bands in the other parts of Tropical Storm Phanfone consisted of showers and lower clouds. Storms in the northwestern part of Phanfone began to generate upper level divergence which pumped mass away to the northwest of the tropical storm.
Tropical Storm Phanfone will move through an environment favorable for intensification during the next few days. Phanfone will move over water where the Sea Surface Temperature is near 29.5°C. It will move south of an upper level ridge. The ridge will produce southeasterly winds which will cause moderate vertical wind shear. Those upper level winds are contributing to the asymmetrical distribution of thunderstorms and the wind shear will inhibit intensification. However, the wind shear could diminish during the next day or two. Tropical Storm Phanfone will gradually intensify and it could strengthen into a typhoon within 48 hours.
Tropical Storm Phanfone will move south of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer Phanfone toward the west-northwest. On its anticipated track Tropical Storm Phanfone will pass north of Palau on Sunday. It could approach the center Philippines within 60 hours. Phanfone could be a typhoon when it gets to the Philippines.