Tag Archives: Wipha

Tropical Storm Wipha Drops Heavy Rain on Vietnam and China

Tropical Storm Wipha dropped heavy rain on parts of northeastern Vietnam and southern China on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Wipha was located at latitude 21.3°N and longitude 107.4°E which put it about 60 miles (95 km) northeast of Hai Phong, Vietnam.  Wipha was moving toward the west-southwest at 10 m.p.h. (16 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 990 mb.

The circulation around Tropical Storm Wipha exhibited much greater organization on Friday even though it was moving close to the coast of southern China.  There was a tighter inner core and more thunderstorms were occurring in the bands revolving around the core.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical storm in all directions.  The appearance of Tropical Storm Wipha on satellite imagery was much more circular and symmetrical.  The strongest winds were occurring in the part of the circulation that was still over water.

Tropical Storm Wipha was being steering slowly toward the west-southwest by a subtropical ridge over China and the adjacent waters of the Western North Pacific Ocean.  The combination of greater organization and slow movement will allow Wipha to drop very heavy rainfall over coastal regions of southern China and northern Vietnam.  Prolonged heavy rain will very likely cause flash flooding in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Francisco was strengthening slowly east-southeast of Iwo To.  At 5:00 p.m. EDT on Friday the center of Tropical Storm Francisco was located at latitude 23.2°N and longitude 149.4°E which put it about 545 miles (880 km) east-southeast of Iwo To.  Francisco was moving toward the northwest at 16 m.p.h. (26 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 995 mb.

Tropical Storm Francisco Forms Northeast of the Marianas

Tropical Storm Francisco formed northeast of the Marianas  on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Francisco was located at latitude 20.4°N and longitude 152.4°E which put it about 800 miles (1290 km) east-southeast of Iwo To.  Francisco was moving toward the northwest at 11 m.p.h. (17 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 998 mb.

A surface low pressure system developed southeast of an upper low north of the Marianas and the Japan Meteorological Agency designated the system as Tropical Storm Francisco.  The distribution of thunderstorms around Francisco was asymmetrical.  Stronger thunderstorms were occurring east of the center of circulation and in a band south of the center of Tropical Storm Francisco.  Bands in other parts of the circulation consisted primarily of showers and lower clouds.  The upper low was producing southwesterly winds which were causing moderate vertical wind shear.  The wind shear was the main factor responsible for asymmetrical distribution of thunderstorms.

Tropical Storm Francisco will move through an environment somewhat favorable for intensification during the next 24 hours.  Francisco will move over water where the Sea Surface Temperature is near 29°C.  The upper low north of the Marianas will continue to cause moderate vertical wind shear during the next day or so.  Tropical Storm Francisco could intensify slowly on Friday.  Francisco will move farther north of the upper low over the weekend.  When it gets farther away from the upper low, the wind shear will diminish and Tropical Storm Francisco could strengthen more quickly.

Tropical Storm Francisco will move southwest of a subtropical ridge over Western North Pacific Ocean.  The ridge will steer Francisco toward the northwest.  On its anticipated track Tropical Storm Francisco could be northeast of Iwo To in about 48 hours.  Francisco could approach southwestern Japan in about fours days.  It is forecast to be a typhoon by that time.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Wipha was moving slowly near the south coast of China.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Wipha was located at latitude 21.1°N and longitude 109.2°E which put it about 25 miles (40 km) south of Beihai, China.  Wipha was moving toward the southwest at 2 m.p.h. (3 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. (80 km/h).  The minimum surface pressure was 990 mb.

Tropical Storm Wipha Brings Wind and Rain to South China

Tropical Storm Wipha brought wind and rain to south China on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Wipha was located at latitude 20.5°N and longitude 110.6°E which put it about 50 miles (80 km) southeast of Leizhou, China.  Wipha was moving toward the west-northwest at 8 m.p.h. (13 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 990 mb.

The circulation around Tropical Storm Wipha contained a large rainband in the southern half of the tropical storm and another large rainband in the northern half of the circulation.  The rainband in the southern half of Wipha brought wind and rain to Hainan Island.  The rainband in the northern part of the tropical storm brought wind and rain to south China including Hong Kong.  Persistent heavy rain was creating the potential for flash floods in parts of southern China.

Tropical Storm Wipha was moving around the southwestern part of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Wipha toward the west-northwest during the next 24 to 36 hours.  On its anticipated track Tropical Storm Wipha will move close to the coast of south China and northeastern Vietnam.  Wipha will continue to bring gusty winds and drop locally heavy rain over those regions on Thursday.

Tropical Storm Wipha Forms South of Macau

Tropical Storm Wipha formed south of Macau late on Tuesday.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Wipha was located at latitude 18.8°N and longitude 112.6°E which put it about 175 miles (285 km) south of Macau.  Wipha was moving toward the northwest at 6 m.p.h. (10 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 994 mb.

The circulation around Tropical Storm Wipha was large, but Wipha did not have a well formed inner core.  Winds to tropical storm force extended out about 200 miles (320 km) from the center of circulation.  However, there were no strong thunderstorms near the center.  Stronger thunderstorms were occurring in bands well to the south and east of the center of circulation.  Bands northwest of the center consisted primarily of showers and lower clouds.

The large lower level circulation of Tropical Storm Wipha was just to the southeast of an upper low over the northwestern part of the South China Sea.  The upper low was circulating some drier air over the northwestern part of Wipha.  It was also causing some vertical wind shear.  The drier air and wind shear were inhibiting the formation of thunderstorms in the northwestern part of Tropical Storm Wipha.

Tropical Storm Wipha will move through an environment somewhat favorable for intensification during the next 24 hours.  Wipha will move over water where the Sea Surface Temperature is near 30°C.  The upper low will continue to inhibit the strengthening of Tropical Storm Wipha.  If thunderstorms begin to develop near the center of Wipha, then the tropical storm could strengthen.

Tropical Storm Wipha will move around the southwestern part of a subtropical ridge over the Western North Pacific Ocean.  The ridge will steer Wipha toward the northwest during the next 24 hours.  On its anticipated track the center of Tropical Storm Wipha will be near the northern part of Hainan Island and the south coast of China in 18 to 24 hours.  Wipha could move more toward the west when it reaches the Gulf of Tongking.  Although Tropical Storm Wipha will bring gusty winds to southern China and northern Vietnam, locally heavy rain and the potential for floods will be greater risks.