Tropical Storm Noul Moves Toward Vietnam

Tropical Storm Noul moved toward Vietnam on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Noul was located at latitude 14.8°N and longitude 113.8°E which put it about 420 miles (675 km) east-southeast of Da Nang, Vietnam.  Noul was moving toward the northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 994 mb.

Tropical Storm Noul moved under the southern portion of a large upper level ridge over Asia and the Western North Pacific Ocean.  The ridge produced strong easterly winds which blew toward the top of Noul’s circulation.  Those winds caused moderate vertical wind shear and they contributed to an asymmetrical distribution of thunderstorms in Tropical Storm Noul.  The strongest thunderstorms were occurring in the western half of Noul.  Bands in the eastern half of the circulation consisted primarily of showers and lower clouds.  Storms near the center of circulation generated upper level divergence which pumped mass away to the west of the tropical storm.  Winds to tropical storm force extended out 140 miles (220 km) from the center of circulation.

Tropical Storm Noul will move through an environment marginally favorable for intensification during the next 24 hours.  Noul will move over water where the Sea Surface Temperature is near 30.5°C.  The upper level ridge will continue to cause moderate vertical wind shear.  The shear will inhibit intensification.  Tropical Storm Noul could strengthen if the wind shear decreases.

The upper level ridge will steer Tropical Storm Noul toward the west-north west during the next day or so.  On its anticipated track Noul will approach the coast of central Vietnam in about 24 hours.  Tropical Storm Noul will bring gusty winds and rain to central Vietnam on Friday.