Tropical Storm Hato Forms Southeast of Taiwan

Tropical Storm Hato formed southeast of Taiwan on Sunday.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Hato was located at latitude 19.6°N and longitude 126.1°E which put it about 390 miles (630 km) east-southeast of Taitung, Taiwan.  Hato was moving toward the west-northwest at 15 m.p.h. (22 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.

A low level center of circulation developed near the western edge of a cluster of thunderstorms southeast of Taiwan and the Japan Meteorological Agency designated the system as Tropical Storm Hato.  The structure of Tropical Storm Hato is very asymmetrical.  Most of the showers and thunderstorms are forming in the western half of the circulation.  There are some very tall strong thunderstorms west of the center of circulation.  An upper level ridge north of Hato is producing easterly winds which  are blowing toward the top of the tropical storm.  Those winds are limiting upper level divergence toward the east and they are probably the reason for the asymmetrical distribution of thunderstorms.

Tropical Storm Hato will move through an environment that will be somewhat favorable for intensification.  Tropical Storm Hato is moving over water where the Sea Surface Temperature is near 31°C.  The upper level ridge is creating moderate vertical wind shear, which is inhibiting intensification.  Tropical Storm Hato is likely to intensify, but it will do so more slowly because of the vertical shear.  Hato does have a chance to strengthen into a typhoon.

Hato is being steered toward the west-northwest by a subtropical ridge north of the tropical storm.  A general west-northwesterly motion is expected to continue for several more days.  On its anticipated track Tropical Storm Hato could reach the islands in the Luzon Strait or southern Taiwan in less than 36 hours.  Hato could make landfall on the east coast of China in less than three days.  Tropical Storm Hato will bring gusty winds and locally heavy rain when it passes near southern Taiwan and the islands in the Luzon Strait.