Tropical Storm Matmo moved over the South China Sea on Friday morning after crossing northern Luzon.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Matmo was located at latitude 17.7°N and longitude 118.7°E which put the center about 120 miles (195 km) west of Vigan, Philippines.  Matmo was moving toward the west-northwest at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 993 mb.

Former Typhoon Matmo weakened back to a tropical storm after it moved across northern Luzon.  A circular eye was still visible at the center of Matmo’s circulation on satellite images.  The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Matmo’s circulation.  Storms near the center of Matmo generated upper level divergence that pumped mass away from the tropical storm.

The circulation around Tropical Storm Matmo was symmetrical.  Winds to tropical storm force extended out 120 miles (195 km) from the center of Matmo’s circulation.

Tropical Storm Matmo will move through an environment favorable for intensification during the next 24 hours.  Matmo will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge that is over China.  The upper level ridge will produce easterly winds that will blow toward the top of Matmo’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Storm Matmo will intensify during the next 24hours.  Matmo is likely to strengthen back to a typhoon later today.

Tropical Storm Matmo will move around the southern side of a high pressure system that is over southern China.  The high pressure system will steer Matmo toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Matmo will pass south of Hong Kong in 24 hours. Matmo will be near Hainan in 36 hours.