When the sun reaches the longitude 105, it is slightly hot. "Twenty-four solar terms": "Summer is also hot, divided into small summer, small at the beginning of the month, large in the month, and still small today." Summer means hot, which means the weather is getting hot, but it is not the hottest, and most parts of the country are basically in line with it.
When the sun reaches the longitude 120, it is the great summer heat. "Tongwei Filial Piety Helps the Gods": "The fifteenth day of Xia Hou is not a big summer, and it is in the middle of June. The small ones and the big ones are extremely hot, and they are divided into sizes. It was small at first, and it became big after reading it. " At this time, before and after the mid-autumn period, most parts of China are the hottest period in a year, and the growth rate of heat-loving crops is also the fastest.
When the sun reaches the longitude 135, it will be beginning of autumn. "Autumn" means cool in summer. In early autumn, Beidou points southwest. From this day on, autumn began, the autumn was crisp, the moon was bright and the wind was clear. Since then, the temperature has gradually decreased from the hottest time.
When the sun reaches longitude 150, it is the heat of the 24 solar terms of the lunar calendar. Summer is a solar term reflecting the temperature change. "Twenty-four solar terms" said: "If you go, you will stop, and the summer will stop here." "Chu" means termination, which means that the summer heat is about to pass, the summer heat will end on this day, and the temperature in most parts of China will gradually drop.