Kirk here. Yesterday I shared an article that gave average temperatures for the past three months. This article gives the averages for August and includes this sentence:

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Temperatures were also extremely unusual. Western Japan experienced sweltering heat day after day, and in Kumamoto, where the Kumamoto earthquake occurred on July 28, the monthly average temperature was 30.8°C—the highest ever recorded in any month since observations began in 1890.
（気温もかなり極端な分布となり、西日本は連日うだるような猛暑が続き、7月28日に熊本地震が発生した熊本では月間平均気温が30.8度と、1890年の観測開始以来通年で観測史上1位の高さとなりました。）
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