A supertyphoon on course to hit Japan over the weekend is as powerful as the deadly storm that ripped through the Philippines in 2013 killing thousands of people, meteorologists said Wednesday

The monstrous storm, named Vongfong, was picking up speed as it churned through the far west of the Pacific Ocean.

"Its strength is very much similar to Haiyan," which ravaged the Philippines in November, said a meteorologist at the Japan Meteorological Agency.

Haiyan left nearly 8,000 people dead or missing when gusts of around 300 kilometres (190 miles) per hour tore through the country, generating giant waves that swamped coastal communities.

Vongfong was registering gusts of the same strength, according to the Japanese agency.

Satellite images of Supertyphoon Vongfong show a perfectly formed eye in the middle of a gigantic swirling disc of cloud that appears to be sucking up weather systems from across the Tropics.

Its present course will see it smash into Japan some time over the weekend, just days after another typhoon whipped through the country, leaving 11 people dead or missing and causing travel chaos.

Vongfong is expected to continue strengthening over the next 24 hours but could lose some steam as it heads north.

"Normally, typhoons are strongest when they are in the Tropics. They start to gradually weaken as they move into the subtropical region and the temperate zone," he said.