Dangerous Super Typhoon Nepartak closed in on Taiwan on Wednesday.  At 11:00 a.m. EDT on Wednesday the center of Typhoon Nepartak was located at latitude 20.5°N and longitude 126.3°E which put it about 480 miles (775 km) southeast of Taipei, Taiwan. Nepartak was moving toward the west-northwest at 19 m.p.h. (31 km/h).  The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 210 m.p.h. (335 km/h).  The minimum surface pressure was 911 mb.

Typhoon Nepartak is the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  The Hurricane Intensity Index (HII) for Nepartak was 40.3.  The Hurricane Size Index (HSI) was 18.8 and the Hurricane Wind Intensity Size Index (HWISI) was 59.1.  These indices mean that Typhoon Nepartak is capable of producing regional catastrophic damage.  As a point of comparison, Typhoon Nepartak is almost as strong as and slightly smaller than Hurricane Rita was when Rita was a Category 5 hurricane over the Gulf of Mexico in 2005.

The circulation of Typhoon Nepartak is very well organized.  It is symmetrical and winds to typhoon force extend out about 45 miles (75 km) from the center.  There is a very small eye at the center of Nepartak and the eye is surrounded by a ring of very strong thunderstorms.  The thunderstorms around the eye are generating strong upper level divergence which is offsetting the flow of mass into the typhoon near the surface.  The upper level divergence is allowing the pressure to stay low and strong winds to persist.  Spiral bands of thunderstorms are rotating around the core of the typhoon.

Typhoon Nepartak is in an ideal environment for a tropical cyclone.  It is moving over water where the Sea Surface Temperature (SST) is near 31°C.  The upper level winds are weak and there is almost no vertical wind shear.  Typhoon Nepartak is likely to maintain its intensity as it approaches the coast of Taiwan.

A subtropical ridge northeast of Nepartak is steering the typhoon toward the west-northwest and that general motion is expected to continue for another 24 to 36 hours.  On its anticipated track Typhoon Nepartak will make landfall along the central portion of the east coast of Taiwan in 12 to 18 hours.  After it moves across Taiwan, Nepartak is expected to make another landfall on the east coast of China.

Nepartak is a strong and dangerous typhoon.  It is capable of causing catastrophic damage over portions of Taiwan.  Nepartak will also produce very rainfall which is likely to cause flash floods and mudslides.  Nepartak will weaken when it moves over Taiwan, but it could still be a typhoon when it reaches the east coast of China.  Nepartak could also bring heavy rain and floods to parts of eastern China.