Tropical Storm Mun was spinning over the Western North Pacific Ocean southeast of Japan on Thursday evening.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Mun was located at latitude 29.9°N and longitude 144.9°E which put the center about 495 miles (795 km) southeast of Tokyo, Japan.  Mun was moving toward the north at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 982 mb.

Tropical Storm Mun strengthened on Thursday as it spun over the Western North Pacific Ocean southeast of Japan.  The circulation around Tropical Storm Mun became more symmetrical.  More thunderstorms developed near the center of Mun’s circulation.  Thunderstorms were also occurring in bands revolving around the center of Tropical Storm Mun.  Storms near the center of Mun generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Storm Mun was small.  Winds to tropical storm force extended out 60 miles (95 km) from the center of Mun’s circulation.

Tropical Storm Mun will move through an environment that will be favorable for intensification during the next 24 hours.  Mun will move over water where where the Sea Surface Temperatures are near 27°C.  An upper level low south of Japan will produce southwesterly winds that will blow toward the top of Mun’s circulation.  Those winds will cause moderate vertical wind shear.  The vertical wind shear will inhibit intensification, but the shear will probably not be enough to prevent intensification.  Tropical Storm Mun is likely to intensify during the next 24 hours.  Mun could strengthen to a typhoon.

Tropical Storm Mun will move around the western end of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Mun toward the northeast during the next 24 hours.  On its anticipated track, Tropical Storm Mun will move farther away from Honshu.

Elsewhere over the Western North Pacific Ocean, Tropical Depression 05W formed south of Taiwan.  At 11:00 p.m. EDT on Thursday the center of Tropical Depression 05W was located at latitude 19.7°N and longitude 118.6°E which put the center about 305 miles (495 km) south-southwest of Kaohsiung, Taiwan.  The tropical depression was moving toward the west-southwest at 7 m.p.h. (11 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 1001 mb.