Tropical Depression 01W formed over the Western North Pacific Ocean south of Pohnpei on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression 01W was located at latitude 5.2°N and longitude 158.2°E which put it about 145 miles (235 km) south of Pohnpei. Tropical Depression 01W was moving toward the west-northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1004 mb.

A low pressure system over the Western North Pacific Ocean south of Pohnpei strengthened on Wednesday morning and both the Japan Meteorological Agency and the U.S. Joint Typhoon Warning Center classified the system as a tropical depression. The circulation around Tropical Depression 01W exhibited more organization on Wednesday morning. Bands of showers and thunderstorms were revolving around the center of Tropical Depression 01W. Storms near the center generated upper level divergence that pumped mass away from the tropical depression.

Tropical Depression 01W will move through an environment favorable for intensification during the next 24 hours. The tropical depression will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis of an upper level ridge over the equatorial Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Depression 01W is likely to intensify to a tropical storm during the next 24 hours.

Tropical Depression 01W will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer the tropical depression toward the northwest during the next 24 hours. On its anticipated track, Tropical Depression 01W will pass west of Pohnpei. The tropical depression could be northeast of Chuuk and east of Fananu on Thursday.