What season is it when it is warm and cold?

It's autumn when it's warm and cold. The weather in autumn is characterized by large temperature difference between day and night and cold in the morning. As the sun rises, the temperature rises rapidly, and it is very hot at noon. This is the meaning of initial warmth. But the high temperature at noon lasts for a short time. As the sun sets or the weather turns cloudy, the temperature will drop rapidly. This is the meaning of cold. Coupled with cloudy days, it rained and the temperature dropped even lower. Therefore, warming first and then cooling refers to the process of autumn temperature from low to high and then to low. It can't mean the whole autumn. Because the whole autumn climate is cold and warm, not warm and cold. Being warm and cold at first doesn't mean spring. Although the climate in spring is really warm and cold all season, the context of this word is obviously not spring. Wild geese fly south, yellow flowers are everywhere, and phoenix trees are raining, which is a typical autumn scenery.