In what season, like the strong wind in spring, comes at night and blows open the petals of ten thousand pear trees?

It's Dong Ji. The time expression of "Hutian August" is clearly written in the poem. August is in Huri, where August is the lunar calendar and the solar calendar is October. Judging from the division of "twenty-four solar terms", "beginning of winter" is beginning of winter, while beginning of winter is in December, so it really belongs to autumn. However, from the climatological point of view, if the average temperature method is used to divide the four seasons, and the average daily temperature for five consecutive days is equal to or lower than 10 degrees Celsius, it is considered to be winter. Judging from the poet's writing background, Hu Tian's snowy area has already entered the cold winter in August. "The north wind rolled the white grass and blew them. Eight In the snow crossed the Tatar sky. Just like the strong wind in spring, it blows at night and blows away the petals of 10 thousand pear trees. " The first four sentences mainly express the scene of flying snow in Hu Tian, comparing flying snow to pear flowers, and comparing the cold scene of heavy snow outside the Great Wall to the warm scene of pear blossoms in spring. When these two images are put together, there is a sharp contrast. On the one hand, they highlight the cold environment outside the Great Wall, on the other hand, they express the poet's inner warmth. While writing "cold" with "warm", they also write "warm" with "cold". Moreover, many descriptions later used this expression. Therefore, judging from the content of poetry and the poet's intention to write poetry, what is described here is that winter is more expressive.