Tropical Storm Co-may formed over the Western North Pacific Ocean west of Luzon on Wednesday.  At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Co-may was located at latitude 17.7°N and longitude 118.7°E which put the center about 150 miles (240 km) west of Vigan, Philippines.  Co-may was moving toward the west at 9 m.p.h. (15 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 992 mb.

A low pressure system over the Western North Pacific Ocean west of Luzon strengthened on Wednesday and the Japan Meteorological Agency designated the system as Tropical Storm Co-may.

The circulation around Tropical Storm Co-may was organizing quickly.  More thunderstorms formed near the center of Co-may’s circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Co-may.  Storms near the center of Co-may generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The strongest winds were occurring in the western side of Tropical Storm Co-may.  Winds to tropical storm force extended out 100 miles (160 km) in the western half of Co-may’s circulation.  The winds in the eastern side of Tropical Storm Co-may were blowing at less than tropical storm force.

Tropical Storm Co-may will move through an environment favorable for intensification during the next 24 hours.  Co-may will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southeastern side of an upper level low that is centered east of Taiwan.  The upper level low will produce southwesterly winds that will blow toward the top of Co-may’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Tropical Storm Co-may will intensify during the next 24 hours.  Co-may could strengthen to a typhoon on Thursday.

Tropical Storm Co-may will get pulled toward the northeast by the much larger circulation around Tropical Storm Francisco.  On its anticipated track, Tropical Storm Co-may will approach northern Luzon in 24 hours.

Tropical Storm Co-may could be a typhoon when it approaches the coast of northwestern Luzon.  Co-may will bring strong winds and locally heavy rain to northern Luzon.  Heavy rain could cause flash floods and mudslides.  Tropical Storm Co-may is likely to cause widespread outages of electricity in northern Luzon.  Co-may could also cause a storm surge of up to 7 feet (2 meters) along the coast of northwestern Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Francisco strengthened a little as it moved toward the southern Ryukyu Islands.  At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Francisco was located at latitude 22.5°N and longitude 129.1°E which put the center about 325 miles (525 km) south-southeast of Okinawa.  Francisco was moving toward the 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 994 mb.