What are some examples of stable and unstable weather?
Unstable air is when cold air overrides warm aire, since cold air is heavier, that is instablility, Between low pressure and high pressure is called a pressure gradient, the tighter the gradient, the more the wind blows. Unstable air is what I mentioned at the beginning, stable air is just the opposite, Cold air on the surface, warm air over it, it can also lead to stagnant air, which can be unhealthy if it stays long enough. Low pressure is like a valley. Most of the time they are attributed with bad weather, but there are a few exceptions, one is a therman low, which causes heat and if you are in that area, you can expect temperatures to be very hot. High pressure is like a mountain, very nice weather can be expected.
