Japan partially lifted wildfire evacuation orders on Friday after rain helped stop the country's worst blaze in more than half a century from spreading.

The fire had raged in the mountains around the city of Ofunato in Iwate Prefecture for over a week, killing one person and forcing more than 4,200 residents to flee their homes.

But wet weather, which began Wednesday following a record dry period, helped firefighting efforts.

"Aerial reconnaissance this morning has not confirmed any spread of fire, fire reaching buildings or white smoke," Toshifumi Onoda, a spokesman for the local fire department, said Friday.

Firefighters were planning to enter forests to check that the fire was put out, he said.

City official Shinichi Matsukawa told reporters that an evacuation order for nearly 1,000 residents had been lifted.

The wildfire engulfed about 2,900 hectares — around half the size of Manhattan — making it Japan's largest in more than 50 years.

It surpassed the 2,700 hectares burnt by a 1975 fire in Hokkaido.

Japan endured its hottest summer on record last year, as climate change pushed up temperatures worldwide.

Then in February, Ofunato received just 2.5 millimeters of rainfall — breaking the previous record low of 4.4 mm for the month, logged in 1967, and far below the average of 41 mm.

At least 78 buildings are believed to have been damaged, although details are still being assessed, according to the fire agency.

The number of wildfires in Japan has declined since peaking in the 1970s.

In Japan, wildfires tend to occur between February and May, when the air dries out and winds pick up. There have been around 1,300 a year in recent years.