Suggestion / Correction
According to the lunar calendar, there are twenty four seasonal divisions. The first day of each season has its a name, which represents the character of the season. 'Li'qiu' is one of them, which literally means "beginning of autumn". The day is usually on August 7th, 8th or 9th by the western calendar.
From Sometime during the day, summer will be over end and autumn is about to will come. However, the weather is will still be hot after the day, and will not immediately become cool. In other words, the weather begins to cool, but just not starting from the day. It begins to cool from mid-August or early September in the northern China, and it begins to change from the early October in the southern China.
(This is a liberal translation of a Chinese text from "http://bitex-cn.com/". I did not post the original text, so just correct my English. Thank you in advance.)
* This sentence was not clear to me, so I changed it based on what I understood from it.