Tropical Storm Hagupit passed well to the south of Guam on Wednesday night. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Hagupit was located at latitude 7.2°N and longitude 142.5°E which put the center about 355 miles (575 km) east-southeast of Yap. Hagupit was moving toward the west at 9 m.p.h. (15 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 1001 mb.
Tropical Storm Hagupit exhibited a little more organization on Thursday morning. Thunderstorms were once again forming in bands in all parts of Hagupit’s circulation. Thunderstorms near the center of Hagupit generated more upper level divergence that pumped mass away from the tropical storm. The removal of more mass caused the surface pressure to decrease slightly.
Even though Tropical Storm Hagupit looked more organized on satellite images, the distribution of wind speeds continued to be asymmetrical. Winds to tropical storm force extended out 115 miles (185 km) in the northern side of Hagupit’s circulation. The winds in the southern half of Tropical Storm Hagupit were blowing at less that tropical storm force.
Tropical Storm Hagupit will move through an environment favorable for intensification during the next 24 hours. Hagupit will move over water where the Sea Surface Temperatures are near 29°C. It will move under the southern part of an upper level ridge that is over the Western North Pacific Ocean. The upper level ridge will produce easterly winds that will blow toward the top of Hagupit’s circulation. Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification. Tropical Storm Hagupit will intensify slowly during the next 24 hours.
Tropical Storm Hagupit will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Hagupit toward the west-northwest during the next 24 hours. On its anticipated track, Tropical Storm Hagupit will approach Yap in 24 hours.
Tropical storm Hagupit will bring strong winds and locally heavy rain to Yap. Heavy rain could cause flash floods in some locations.