Why Do We Call Them the ‘Dog Days’ of Summer?
It doesn’t have to do with dogs lying around in the heat—the phrase comes from ancient Greek beliefs about a star.
By Becky Little, National Geographic
I find a similar comment in a traditional Arabic/Ishmaelitic text which follows: الشعرى هو النجم المضيء الذي يخرج في شدة الحر. It means Sirius is a bright star which appears in extremely hot weather.