What does it mean that the remnants gather in summer and the new rain brings autumn haze?

"Residual clouds gather summer heat, and new rain brings autumn haze" means: the weather in summer is changeable. After a heavy rain, the summer heat disappeared and the weather began to cool slowly. The drizzle is tinged with autumn fog. These two poems, "Remnant clouds receive summer heat, and new rain brings autumn haze", come from "On June 30th, Shuige sent Wang Huaying Shaofu back to the county". The author of this poem is Cen Can, a frontier poet in Tang Dynasty. He studied with his brother since childhood and read all the history books.

The original poem "On June 30th, Shuige sent Wang Huaying Shaofu back to the county" is: People will leave the pavilion at night, and the wine in the pool will not get drunk. Close the door and dream, and the fairy palm will take you back. Lotus leaf fish boat, rattan flower hairpin. The remnants gather in the summer heat, and the new rain brings autumn haze. I don't know what to do when I get lost, and I can't bear to think about it. There is no Xiaojiangtan in Lei Ziting's house.

Among them, the two poems, Remnant Clouds Harvest Summer Heat, and New Rain Bring Autumn Lan, describe the scene of midsummer, alternating autumn and winter, and capture the climate characteristics in late summer and early autumn, which are very specific.