Tropical Storm Neoguri formed east of northern Luzon on Thursday. At 5:00 p.m. EDT on Thursday the center of Tropical Storm Neoguri was located at latitude 20.1°N and longitude 129.4°E which put it about 470 miles (755 km) south-southeast of Okinawa and about 500 miles (800 km) east-northeast of the northern end of Luzon. Neoguri was moving toward the north-northwest at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 997 mb.
A distinct low level center of circulation developed on the western side of a cluster of thunderstorms east of northern Luzon on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Neoguri. The circulation around Neoguri exhibited much more organization. The inner part of a rainband wrapped around the center of circulation. A broken ring of thunderstorms formed around the southwestern half of the center and an elliptical eyelike feature appeared on microwave satellite images. The long axis of the elliptical eye was oriented northeast to southwest. Bands of showers and thunderstorms developed in the eastern half of Tropical Storm Neoguri. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Thunderstorms near the center generated upper level divergence which pumped mass away to the northeast of the tropical storm.
Tropical Storm Neoguri will move through an environment mostly favorable for intensification during the next 24 to 36 hours. Neoguri will move over water where the Sea Surface Temperature is near 28°C. It will move under the western part of an upper level ridge where the winds are weaker. There will not be a lot of vertical wind shear during the next 24 hours. There appears to be drier air to the northwest of Tropical Storm Neoguri, which may be the reason why the rainbands in the western half of the circulation are weaker. If Neoguri pulls drier air into the core of the circulation, then that would inhibit intensification. On the other hand, if an eye does form completely, then Tropical Storm Neoguri could strengthen into a typhoon.
The future track of Tropical Storm Neoguri will depend on how strong it becomes. If Neoguri strengthens, then a trough over China will likely steer the tropical storm toward the northeast. However, if drier air gets pulled into the core of the circulation, then a weaker Tropical Storm Neoguri would be steered by winds closer to the surface. A high pressure system over the Western North Pacific would steer Tropical Storm Neoguri toward the west. Guidance from numerical models is split between these two scenarios. Some models forecast a track toward the northeast and other models predict a track toward the west. Tropical Storm Neoguri did not move much on Thursday and either scenario is possible.