Tag Archives: North Korea

Typhoon Bavi Passes East of Shanghai

Typhoon Bavi passed east of Shanghai on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Typhoon Bavi was located at latitude 31.9°N and longitude 124.7°E which put it about 200 miles (320 km) east-northeast of Shanghai, China.  Bavi was moving toward the north-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 958 mb.

The circulation around Typhoon Bavi was well organized on Tuesday.  A circular eye with a diameter of 18 miles (30 km) was at the center of Bavi.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Typhoon Bavi.  Storm near the core generated upper level divergence which pumped mass away to the north of the typhoon.

The circulation around Typhoon Bavi was moderately large.  Winds to typhoon force extended out 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Bavi was 19.2.  The Hurricane Size Index (HSI) was 16.0 and the Hurricane Wind Intensity Size Index (HWISI) was 35.2.  Typhoon Bavi was capable of causing regional serious damage.

Typhoon Bavi will move through an environment favorable for intensification during the next 12 hours.  Bavi will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Bavi could strengthen into the equivalent of a major hurricane during the next 12 hours.  In 12 hours Bavi will start to move over cooler water, which could end the chance for intensification.  In 24 hours Typhoon Bavi will approach the eastern part of an upper level trough over China.  The trough will produce strong southwesterly winds which will cause strong vertical wind shear.  The strong shear will cause Bavi to weaken more quickly.

Typhoon Bavi will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean.  The high will steer Bavi toward the north during the next 36 hours.  On its anticipated track Typhoon Bavi could approach the west coast of North Korea in about 24 hours.  Bavi will bring strong winds and locally heavy rain to North Korea and parts of northeastern China.

Typhoon Chan-hom Approaching Shanghai

Large Typhoon Chan-hom is moving northward toward Shanghai, China.  At 5:00 p.m. EDT on Friday the center of Typhoon Chan-hom was located at latitude 28.2°N and longitude 123.1°E which put it about 300 miles (500 km) south-southeast of Shanghai, China.  Chan-hom was moving to the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 956 mb.

Chan-hom still has a very symmetrical circulation, but the intensity of the thunderstorms appears to have weakened in recent hours.  The typhoon is moving over water where the Sea Surface Temperatures (SSTs) are cooler and that is the most likely cause for the decreased intensity of the thunderstorms.  As it nears the coast of China, more of the western half of the circulation will be over land and increased friction will further reduce the wind speeds.  Vertical wind shear may also increase as Chan-hom moves farther north.

Chan-hom is moving around the western end of the subtropical ridge which has been steering it toward the northwest.  As it moves around the end of the ridge, Chan-hom will first turn toward the north and then it could accelerate toward the northeast when it begins to be affected by the mid-latitude westerlies.  On its anticipated track the center of Chan-hom will be near Shanghai in about 24 hours.  Given the large size of Chan-hom, the typhoon could bring strong winds and locally heavy rain to the region near Shanghai.