Tropical Storm Yagi dropped heavy rain on parts of northern Luzon on Monday.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Yagi was located at latitude 17.5°N and longitude 121.7°E which put the center about 25 miles (40 km) south of Tuguegarao, Philippines.  Yagi was moving toward the north-northwest 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 996 mb.

The center of Tropical Storm Yagi moved across northern Luzon on Monday.  Storms near the center of Yagi’s circulation dropped heavy rain on parts of northern Luzon.  There were reports that heavy rain caused floods and landslides in some locations.  There were also reports that the floods and landslides caused an unknown number of deaths.

The circulation around Tropical Storm Yagi weakened gradually as Yagi move across northern Luzon.  Thunderstorms were still occurring near the center of Yagi’s circulation.  Thunderstorms were also occurring in bands revolving around the center of circulation.  Storms near the center of Yagi generated upper level divergence that pumped mass away from the tropical storm.

Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Storm Yagi.

Tropical Storm Yagi will move around the western part of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Yagi toward the northwest during the next 24 hours.  On its anticipated track, the center of Tropical Storm Yagi will move over the South China Sea in 12 hours.  A second high pressure system that is over China will steer Yagi toward the west on Tuesday.

Tropical Storm Yagi will continue to weaken gradually during the next few hours while it moves across northern Luzon.  Yagi will move into an environment that will be favorable for intensification when it moves over the South China Sea.  Yagi will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the South China Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Storm Yagi is likely to intensify after it moves over the South China Sea.  Yagi is likely to strengthen to a typhoon by the middle of the week.

Tropical Storm Yagi will continue to drop heavy rain over northern Luzon during the next few hours.  Heavy rain is likely to cause additional floods and landslides.