Dogs of summer? 夏の犬たち？

Definition

the dog days of summer : the hottest part of summer, occurring in July and August

the dog days of summer : 夏の一番暑い時期

Example

Ex.)During the dog days of summer, it’s good to learn a new language while cooling down in doors.

 夏の暑い日には、屋内で涼みながら新しい言語を学ぶのもいいよね。