Why is the person's mood as sunny as the weather?

I think this should be related to your mood, not the weather depends on your mood. If you are happy that day and something pleasant happens, even if it rains cats and dogs, it will not affect your happy mood at all. Maybe you think raindrops are dancing for you. Of course, when you are sad and depressed, even in the hot sun, you will feel that sunny days are not good. I think it's because you haven't started a day's work. For example, if you open the curtains early in the morning and see that it is raining outside, at this time, external factors directly cause a series of troubles that rain will bring to your brain. For example, pants are easy to get wet, it is also very troublesome to take a bus, and you have to take an umbrella wherever you go. These thoughts will unconsciously sneak into your mind, causing aversion to rainy weather, which is why you have this problem. Your mood is the most regulated.