Tropical Storm Choi-wan Brings Rain to Philippines

Tropical Storm Choi-wan brought rain to the central Philippines on Tuesday. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Choi-wan was located at latitude 13.1°N and longitude 121.9°E which put it about 155 miles (250 km) southeast of Manila, Philippines. Choi-wan was moving toward the west-northwest at 17 m.p.h. (28 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 1002 mb.

The center of Tropical Storm Choi-wan made an initial landfall on the east coast of Samar and then it moved west-northwest across the central Philippines. Choi-wan moved across the Sibuyan Sea and it was centered southeast of Manila on Tuesday night. The circulation around Tropical Storm Choi-wan weakened when the center passed over Samar, but it was still producing a small area of tropical storm force winds. Winds to tropical storm force extended out 35 miles (55 km) from the center of Choi-wan.

Tropical Storm Choi-wan dropped locally heavy rain over parts of Samar, Masbate, Panay and Mindoro on Tuesday. An upper level ridge centered over southern China was producing northeasterly winds which were blowing toward the top of Choi-wan. Those winds were producing moderate vertical wind shear and they causing the heavier rain to fall in bands in the southern half of Tropical Storm Choi-wan. Bands in the northern half of the tropical storm consisted primarily of showers and lower clouds.

Tropical Storm Choi-wan will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Choi-wan toward the north-northwest during the next several days. On its anticipated track the center of Tropical Storm Choi-wan could pass just south of Manila in 12 hours. Choi-wan could drop locally heavy rain on Mindoro and western Luzon. Heavy rain could cause flash floods in some locations.

Tropical Storm Choi-wan will move through an environment that is mostly unfavorable for intensification. Choi-wan will move over water where the Sea Surface Temperatures are near 30°C. However, the upper level ridge center over southern China will continue to cause moderate vertical wind shear. The wind shear will limit the potential for intensification. The eastern side of the circulation around Tropical Storm Choi-wan will be over Luzon during the next 24 hours, which will also be unfavorable for intensification.