Tag Archives: Tropical Storm Sanvu

Tropical Storm Sanvu Spins Northeast of Chuuk

Tropical Storm Sanvu was spinning over the Western North Pacific Ocean northeast of Chuuk on Friday morning. At 5:00 a.m. EDT on Friday the center of Tropical Storm Sanvu was located at latitude 10.2°N and longitude 156.0°E which put it about 345 miles (555 km) northeast of Chuuk. Sanvu was moving toward the northwest at 3 m.p.h. (5 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 Sanvu strengthened during Thursday. More thunderstorms developed near the center of Sanvu’s circulation. Storms near the center of circulation generated upper level divergence that pumped mass away from the tropical storm. Even though Tropical Storm Sanvu strengthened, the distribution of thunderstorms became more asymmetrical. Most of the thunderstorms were occurring in bands in the eastern side of Sanvu’s circulation. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Storm Sanvu.

Tropical Storm Sanvu will move through an environment that will become unfavorable for intensification during the next 24 hours. Sanvu will move over water where the Sea Surface Temperatures are near 29˚C. However, it will move under the northern side of an upper level ridge over the equatorial Western North Pacific. The ridge will produce westerly winds that will blow toward the top of Sanvu’s circulation. Those winds will cause the vertical wind shear to increase. Stronger vertical wind shear is likely to cause Tropical Storm Sanvu to start to weaken during the next 24 hours.

Tropical Storm Sanvu will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Sanvu toward the west-northwest during the next 24 hours. On its anticipated track, Tropical Storm Sanvu will pass north of Chuuk and Fananu during the weekend.

Tropical Storm Sanvu Develops Northwest of Pohnpei

Tropical Storm Sanvu developed over the Western North Pacific Ocean northwest of Pohnpei on Wednesday night. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Sanvu was located at latitude 9.3°N and longitude 156.8°E which put it about 165 miles (265 km) north-northwest of Pohnpei. Sanvu was moving toward the northwest at 16 m.p.h. (26 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 1000 mb.

Former Tropical Depression 01W strengthened on Wednesday night and the Japan Meteorological Agency designated the system as Tropical Storm Sanvu. The inner end of a rainband wrapped around the center of Sanvu’s circulation. Other bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 60 miles (95 km) from the center of circulation.

Tropical Storm Sanvu will move through an environment favorable for intensification during the next 24 hours. Sanvu will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis of an upper level ridge over the equatorial Western North Pacific Ocean. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Storm Sanvu could intensify during the next 24 hours. Sanvu will move under the northern side of the upper level ridge on Friday and the vertical wind shear will increase. Tropical Storm Sanvu is likely to weaken when the wind shear increases.

Tropical Storm Sanvu will move around the southern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Sanvu toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Sanvu will move farther away from Pohnpei. Sanvu will be northeast of Chuuk and Fananu on Thursday evening.

Tropical Storm Sanvu Forms Over Northern Marianas

Tropical Storm Sanvu formed over the northern Marianas on Monday.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Sanvu was located at latitude 20.4°N and longitude 146.4°E which put it about 100 miles (160 km) north-northeast of Agrihan.  Sanvu was moving toward the north-northeast at 3 m.p.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.

Tropical Storm Sanvu developed when a distinct center of circulation formed within a much larger area of low pressure over the northern Marianas.  The circulation of Sanvu is still in the early stages of consolidation around the center.  Most of the showers and thunderstorms were forming in bands in the southern half of the circulation.  The bands in the northern half of the circulation were weaker.  The showers and thunderstorms south of the center were beginning to generate some upper level divergence which was pumping mass away to the south of the tropical storm.

Tropical Storm Sanvu will be moving through an environment that is somewhat favorable for intensification.  Sanvu will move over water where the Sea Surface Temperature is near 30.5°C.  Sanvu is under the axis of a narrow upper level ridge and the winds over the southern half of the circulation are fairly weak.  There is little vertical wind shear over that part of the tropical storm.  An upper level trough north of the ridge is producing stronger winds over that half of the circulation.  The stronger winds may be responsible for the lack of strong rainbands in the northern half of Sanvu.  The trough is forecast to move east and the shear in that region should decrease.  When the shear decreases Sanvu could intensify at a faster rate and it is forecast to become a typhoon in two or three days.

The trough is currently steering Tropical Storm Sanvu slowly toward the north-northeast.  When the trough moves away to the east a ridge if forecast to steer Sanvu more toward the north.  On its anticipated track Tropical Storm Sanvu will gradually move away from the northern Marianas and the weather should improve in that region.