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Typhoon In-Fa Brings Wind and Rain to Ryukyu Islands

Typhoon In-Fa brought gusty winds and locally heavy rain to the Ryukyu Islands on Friday. At 11:00 a.m. EDT on Friday the center of Typhoon In-Fa was located at latitude 25.1°N and longitude 124.9°E which put it about 30 miles (50 km) northwest of Hirara, Japan. In-Fa was moving toward the northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 969 mb.

The slow movement of Typhoon In-Fa during the past several days and its large size caused In-Fa to mix cooler water to the surface in a large area. The cooler water meant that In-Fa extracted less energy from the ocean and thunderstorms weakened in parts of the circulation around the typhoon. There was still a large circular eye with a diameter of of 65 miles (105 km) at the center of Typhoon In-Fa. The eye was surrounded by a broken ring of thunderstorms and the strongest winds were occurring in the broken ring of storms. Bands of showers and thunderstorms continued to revolve around the center of In-Fa. Storms near the center of circulation generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon In-Fa was large. Winds to typhoon force extended out 80 miles (130 km) from the center of In-Fa. Winds to tropical storm force extended out 270 miles (435 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon In-Fa was 11.5. The Hurricane Size Index (HSI) was 31.7 and the Hurricane Wind Intensity Size Index (HWISI) was 43.2.

Typhoon In-Fa will move through an environment somewhat favorable for intensification during the next 24 hours. Once the center of In-Fa moves away from the cooler water mixed to the surface, the typhoon will move over water where the Sea Surface Temperatures are near 28°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. The large size of Typhoon In-Fa will mean that intensification could be slow to occur. Typhoon In-Fa could strengthen during the next 24 hours.

Typhoon In-Fa will move around the southwestern part of a high pressure system over the Western North Pacific Ocean during the next 36 hours. The high will steer In-Fa toward the northwest. On its anticipated track Typhoon In-Fa will move slowly away from the Ryukyu Islands. Since the circulation around In-Fa is so large, the typhoon will continue to produce gusty winds and locally heavy rain for another 24 hours. The center of Typhoon In-Fa could approach the east coast of China south of Ningbo in 48 hours.