Tropical Storm Ewiniar strengthened near Manila on Saturday night. At 11:00 p.m. EDT on Saturday the center of Tropical Storm Ewiniar was located at latitude 14.3°N and longitude 121.4°E which put it about 50 miles (80 km) southeast of Manila, Philippines. Ewiniar was moving toward the northwest at 6 m.p.h. (10 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 990 mb.

Former Tropical Depression 01W strengthened over southern Luzon on Saturday night and the Japan Meteorological Agency designated the system as Tropical Storm Ewiniar. The circulation around Tropical Storm Ewiniar was very symmetrical. Thunderstorms were occurring near the center of Ewiniar’s circulation. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center of Ewiniar 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 Ewiniar was relatively small. Winds to tropical storm force extended out 60 miles (95 km) from the center of Ewiniar’s circulation.

Tropical Storm Ewiniar will move through an environment that will be mostly favorable for intensification during the next 24 hours. Ewiniar will move over water where the Sea Surface Temperatures are near 31°C. It will move under the western part of an upper level ridge over the Western North Pacific Ocean. The upper level ridge will produce southerly winds that will blow toward the top of Ewiniar’s circulation. Those winds will cause some vertical wind shear, but the shear will not be strong enough to prevent intensification. Even though part of the circulation around Tropical Storm Ewiniar will pass over Luzon, Ewiniar is likely to intensify during the next 24 hours.

Tropical Storm Ewiniar will move around the western end of a high pressure system that is east of the Philippines. The high pressure system will steer Ewiniar toward the north during the next 24 hours. On its anticipated track, Tropical Storm Ewiniar will move along the east coast of Luzon during the next 24 hours. Ewiniar will start to move toward the northeast on Monday after is moves around the western end of the high pressure system.

Tropical Storm Ewiniar will continue to produce strong winds and locally heavy rain in Luzon during the next 24 hours. Heavy rain is likely to cause flash floods in some locations. Ewiniar could also produce a storm surge of up to 7 feet (2 meters) along the east coast of Luzon where the wind blows the water toward the shore.