YOU SAID:

It was the beginning of what would become the hottest day on record.

INTO JAPANESE

それは記録的に最も暑い日になるものの始まりでした。

BACK INTO ENGLISH

It was the beginning of what is recordably the hottest day.

INTO JAPANESE

これは記録的に最も暑い日の始まりでした。

BACK INTO ENGLISH

This was the beginning of the hottest day on record.

INTO JAPANESE

これは記録上最も暑い日の始まりでした。

BACK INTO ENGLISH

This was the beginning of the hottest day on record.