TOKYO - The Japanese archipelago experienced another day of sweltering heat Wednesday, with the mercury topping 40 C for a record 10th day this year, the weather agency said.

Hakata Ward in the southwestern city of Fukuoka saw the temperature hit 40.4 C, caused by hot, moist air from a typhoon flowing into the surrounding region, the Japan Meteorological Agency said.

Across the nation, 246 of 914 observation points reported 35 C or higher during the day, crossing the threshold of "extremely hot." When the mercury tops 40 C, it is classified as "cruelly hot."

In Dazaiufu, Fukuoka, 40.3 C was recorded. The city is known for Dazaifu Tenmangu, a Shinto shrine and major tourist draw.

The weather agency expects high temperatures will continue for about a month, advising people to stay hydrated and avoid heat sickness.

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