Powerful Typhoon Hinnamnor is slowly moving toward Okinawa from its current location to the south of the prefecture, with stormy weather set to hit on the weekend.

The typhoon is forecast to approach the Sakishima Islands — which include Miyako and Ishigaki islands — on Saturday evening, with the Meteorological Agency warning of strong gusts and high waves for the southernmost prefecture.

As of noon, Hinnamnor was located around 320 kilometers south-southeast of Ishigaki Island. It had an atmospheric pressure of 935 hectopascals at its center and was packing winds of up to 234 kph.

It is expected to move north into the East China Sea from Sunday through Monday, and approach Kyushu on Tuesday.

The typhoon, the 11th named storm of the season, is expected to pack winds of up to 234 kph around the Sakishima Islands and 108 kph near Okinawa's main island on Saturday. Conditions are expected to worsen on Sunday, with winds of up to 252 kph whipping the Sakishima Islands and up to 126 kph hitting the prefecture's largest island.

Heavy rain is also predicted across much of Japan's main islands due to a stationary front, with the agency warning of landslides, flooding and rising rivers. There are also concerns about potential lightning strikes, strong winds and even tornadoes.

According to a forecast for the 24 hours through Saturday morning, 120 millimeters of rain is expected in the Tokai central region and 80 mm in the Kinki region — which includes Osaka, Kobe and Kyoto — and the Sakishima Islands.

In the following 24 hours, there is 200 to 300 mm of rainfall predicted across the Sakishima Islands, 100 to 150 mm in the Tokai region and Okinawa's main island, and between 50 and 100 mm in the Kinki region.

The weather agency downgraded the typhoon to "very strong" from "violent" at 3 a.m. Friday.