Tropical Depression Forms Southeast of Guam, Warning Issued

Tropical Depression 06W formed southeast of Guam on Sunday night and a Tropical Storm Warning was issued for Guam. At 5:00 a.m. EDT on Monday the center of Tropical Depression 06W was located at latitude 12.1°N and longitude 146.0°E which put it about 160 miles (260 km) southeast of Guam. Tropical Depression 06W was moving toward the west-northwest at 13 m.p.h. (20 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 1000 mb.

A Tropical Storm Warning was issued for Guam. A Tropical Storm Watch was issued for Rota.

A circulation center developed in a cluster of thunderstorms southeast of Guam on Sunday night and the Joint Typhoon Warning Center designated the system as Tropical Depression 06W. The distribution of thunderstorms around Tropical Depression 06W was asymmetrical. The strongest thunderstorms were occurring in bands on the eastern side of the tropical depression. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Storms near the center of Tropical Depression 06W began to generate upper level divergence that pumped mass away from the tropical depression.

Tropical Depression 06W will move through an environment that is somewhat favorable for intensification during the next several days. The depression will move over an area where the Sea Surface Temperatures are near 29°C. It will move south of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will blow toward the top of Tropical Depression 06W. Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification. The tropical depression will move into an area where drier air is sinking toward the surface. The drier air will limit the formation of thunderstorms on the western side of the circulation and it will inhibit intensification. Tropical Depression 06W is forecast to intensify to a tropical storm during the next 24 hours.

Tropical Depression 06W will move around the western side of a subtropical high pressure system over the Western North Pacific Ocean. The high will steer the depression toward the northwest during the next 24 hours. On its anticipated track Tropical Depression 06W will pass near Guam in 12 hours. The tropical depression will bring gusty winds and heavy rain to parts of Guam. It will move more toward the north when it reaches the western end of the high pressure system.