The heat wave continues in Tokyo on Aug. 1. (Ikuro Aiba)

Japan recorded the hottest daily average temperature of any July in the nation's record history, according to Japan Meteorological Agency data. 

The high daily temperature surpassed the scorching heat of 2023, when the term “global boiling” became a hot topic, and set a new record for the second year in a row. 

According to the JMA, this summer’s heat is due to a strong high-pressure system in the Pacific Ocean, westerly winds bringing warm air and the long-term rise in temperatures due to global warming.

“Like last year, conditions have combined to produce record high temperatures, and we expect the heat to continue through August and beyond,” said Masayuki Hirai, head of the JMA's climate information division’s forecast team.

The Asahi Shimbun examined temperatures at 15 stations that are less affected by urbanization and are used by the JMA as a benchmark for average temperatures in Japan.

They include cities such as Yamagata city, Choshi in Chiba Prefecture, and Miyazaki city.

Average July temperatures have been calculated for each year based on average temperatures for July 1-31 since 1898, when such data became available.

This year, the average July temperature was 26.22 degrees, the hottest on record.

Except for a few dips in the middle of the month, when there was heavy rainfall in western Japan, and the end of the month, when the Tohoku region was hit by torrential rains, the average temperature across the country was higher than on the same days in the past.

The average daily temperature in July 2023 was 25.96 degrees, which broke the record set in 1978 for the first time in 45 years.

The average temperature in July 2022 was 25.24 degrees, the seventh highest on record, while the average in 2021 was 25.15 degrees, the eighth highest on record.

The average July temperature has fluctuated from year to year, but has risen about 1.5 degrees over the past 127 years.

Urban areas susceptible to the heat island effect are getting even hotter.

A survey of four observation centers—Tokyo’s Chiyoda Ward, Nagoya’s Chikusa Ward, Osaka’s Chuo Ward and Fukuoka’s Chuo Ward—shows that the average temperature for July this year was 29.42 degrees, exceeding the previous record in 1994 of 29.18 degrees.

The average July temperature at these four locations has risen about 2.4 degrees over the past 127 years.

Global average temperatures have also been at an all-time high for 13 consecutive months until June of this year.