There’s a Japanese proverb that goes, “Onna gokoro to aki no sora.” It translates as “A woman’s heart and the autumn sky” but it is used to mean something like, “A woman’s feelings and the autumn weather are as fickle as each other.”
It’s probably fair to assume that a man came up with this proverb, and that its usage might be less well-received these days than in the past. Even so, I have to say that a bit of fickleness or variation in the sky would be very welcome right now. After months of oppressive summer heat, it would be nice to feel the sun’s rays coming in at a different angle, which would indicate the transition into autumn.
It may be that you look out of the window one morning in September and notice the beginnings of a reddish tinge on the momiji (maple leaves). You may feel a chill from an evening breeze, bringing a presentiment of the colder weather to come. I’d just settle for a few days when I don’t have to use my air conditioner.