People cool off in Kofu town of Yamanashi prefecture yesterday as a heatwave stifled Japan with temperatures topping 40 degrees Celsius in two cities.

A heatwave stifled Japan yesterday as the temperature topped 40 degrees Celsius in two cities, leaving at least four people dead over the weekend, officials and reports said. The Japan Meteorological Agency said the temperature reached 40.6 C in Kofu, 100km west of Tokyo, in mid-afternoon.

The weather agency had warned earlier in the day that the temperature would soar past 35C in 39 of the country’s 47 prefectures. It warned people to drink plenty of water and use air-conditioners.

On Saturday, the mercury topped 40 C for the first time in Japan since August 2007, when it had reached an all-time high of 40.9 C in two separate cities.

An 84-year-old woman and a 66-year-old man in western Japan died from heat stroke on Saturday after they were found collapsed in fields, Kyodo news agency said.

Two more deaths from heat stroke were confirmed by officials yesterday.

An 80-year-old woman died in hospital after she was found collapsed at her wooden home yesterday morning in Arita, a city south of Osaka, a medical evacuation official said. The living room where she was found was not air-conditioned.

In Saitama north of Tokyo, a 60-year-old man died in hospital after he was found unconscious on a street Saturday afternoon.

The heatwave, also gripping parts of China, has been caused by a Pacific high pressure system covering most of the Japanese islands, the weather agency said.

In early July a heatwave in the country claimed at least a dozen lives, according to media reports.

Seoul warns of power shortages amid nuclear shut downs

South Korea has warned of serious power shortages this week amid an expected rise in summer temperatures and as the resources-starved country struggles to keep up with demand after six nuclear plants have gone off-line, Reuters reports from Seoul.

The energy ministry said it may take emergency measures such as rolling power cuts to avoid a repeat of 2011 blackouts which cut electricity to businesses and homes across the country.

Separately, the ministry said some major companies, including Kia Motors Corp and Hyundai Motor Co, had not complied with energy saving regulations such as cutting power consumption during peak hours.

Both automakers refused to comment on the matter.

Of the country’s total 23 reactors, six units are currently off line - three for maintenance or expiry of operational approval, and the other three to replace cables supplied with fake certificates.

 Oil, gas and coal produce most of South Korea’s electricity, but nuclear plants generate more than 30% of power.

“If one nuclear reactor stops its operation all of a sudden, we may have to start rolling power blackouts like we did on September 15, 2011,” Energy Minister Yoon Sang-jick told a news conference.

Rolling blackouts would initially affect residential areas, minimising any impact on the country’s export-focused businesses.

South Korea’s power demand is projected to peak at up to 80,500 megawatts (MW) in the next three days while its power supply capacity is seen at 77,440 MW, the energy ministry said in a statement. With all the possible power-saving and supplying measures, the supply surplus could be raised to 1,800 MW but that would still not be enough, it added.

South Korea has carried out power saving measures in the past such as encouraging offices and households to use less air-conditioning.