Why does the highest temperature appear in the valley during the day and the lowest temperature in the mountains at night?

This is due to geological structure and physical phenomena. The air in the valley flows slowly. Under the action of sunlight, the temperature has a cumulative effect, which leads to a higher temperature in the valley during the day. At night, because the valley lost the heating effect of sunlight, the air gradually became cold, and the proportion of cold air was greater than that of hot air, so cold air gradually deposited in the valley, resulting in the lowest temperature in the valley at night.

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