Beijing in July or August, which month is better?

It is suggested that August is better, especially after beginning of autumn, otherwise it will catch up with the dog days in July, and the sauna days in Beijing will be very uncomfortable. After beginning of autumn, I passed the hottest and most uncomfortable head and the second volt, so sweat won't make me sticky, and I won't feel out of breath when I am in the sauna. The most obvious thing is that after beginning of autumn, even if the weather is very hot, hiding in the shade can keep you cool, but hiding in the shade in sauna days will still stick and sweat.