The rainy season started in Okinawa Prefecture and a neighboring area Friday, eight days later than in an average year and 10 days later than last year, the Okinawa Meteorological Observatory said.

The weather over the area is expected to remain unsettled for a week due primarily to a rain front over the sea off Okinawa, the observatory said.

A weak tropical cyclone located south of Okinawa grew into a typhoon Friday morning.

The typhoon, this year's second, has an atmospheric pressure of 998 hectopascals at its center and winds up to 64.8 kph, it said.