Japan recorded a temperature of 40 C for the first time this year on Sunday, with the mercury hitting the scorching level in central Japan as a heatwave continues to engulf the nation, according to the weather agency.

With a high-pressure system hovering over wide areas, Shizuoka reported 40.0 C at 1:18 p.m., and temperatures had risen to 35 C or above at 168 locations among the Japan Meteorological Agency's 914 observation points nationwide by 1 a.m.

Shimonita, Gunma Prefecture, logged 39.8 C, followed by 38.8 C in Hamamatsu, Shizuoka Prefecture, Otsuki, Yamanashi Prefecture, and Namie, Fukushima Prefecture.

The temperatures in Shizuoka, Shimonita and Namie were record highs for the locations. The temperature in Tokyo, meanwhile, stood at 34.4 C.

The agency has issued an alert against heat exhaustion for much of the archipelago, urging people not to go outside during the day as much as possible and use air conditioning when inside.