I was wondering what exactly triggers clouds to rain and how heavy the rain is. I live in a mountain region, so i heart the terms of clouds being too heavy and low, so they get stuck and rain off. But that doesn’t feel to be entirely true and more of a folks tale.
So how does it happen?
In: Physics
Clouds are water vapor suspended in air. The amount of water vapor air can hold depends on the temperature and pressure of the air. As the air raises, the temperature and pressure (generally) decrease. As temperatures decrease, the air can hold less water vapor. As pressure decreases, the air can hold more water vapor. Rain is caused when those properties change in such a way that the air currently holds more vapor than it is capable of, causing condensation.
It rains on the rainward side of a mountain because as elevation rises, temperatures drop so quickly it overpowers the effects of the drop in pressure. Once the air gets over the mountain, to the leeward side, it begins to warm, so it can hold more water vapor and stops condensing.
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