Ever hear your local TV weatherpeople preface a warning of bad weather by mentioning "spin" in the atmosphere as a culprit? What they really mean is that parcels of air at high altitude are moving in such a way as to create a net upward movement of air. In other words, forces aloft are causing lift at the surface. And you know what that means when unstable conditions are present: Rising air cools, saturates, gives off latent heat, and keeps on rising. The end result can be heavy precipitation and thunderstorms. So the lesson here is simple-"spin" can be bad news.
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