Did it snow in Sulan, Gansu on July 22nd?

Weather forecast for July 22nd in Lanzhou, Gansu: the highest temperature is 22, and the lowest is 17.

The conditions for snow are: the atmosphere needs to contain cold ice crystal nuclei. A lot of water vapor. Below 3.0℃ (freezing point). If the cold air is quite strong and carries moisture, it can snow at the temperature of 1℃ to 10℃.