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So those are your two primary causes for, and then a tertiary cause would be dry air intrusion. So for example, hurricanes that are closer to, or tropical systems I should say, that are closer to drier areas. So in the Gulf for example, hurricanes in the Gulf of Mexico or wherever, as they move towards the Gulf Coast, if they're further west, so they're closer to Texas or Mexico, they tend to actually, it's not always the case, but generally speaking they do tend to lose energy as they're beginning to make landfall because they dry in more dry air from the continental land mass. The air is typically drier in west Texas and that part of Mexico than it is in east Texas. So there's less moisture to work with, this dry air gets in there and you have evaporational cooling which actually negatively affects it because it cools the air instead of warming the air and it changes the density factor, it makes it more heavy. So that's not what hurricanes or tropical systems want. And again, when hurricanes move into the Carolinas you see the eyewall sort of, you lose that nice closed concentric eyewall and it becomes like a half moon shape where half of it becomes open, the other half is closed, and again there's dry air intrusion from land. So the primary thing is losing your heat energy source and your source of moisture. A secondary factor is friction, slowing down the air just enough that the parcels get bounced in a weird way so they can't fully saturate. And the third factor is dry air intrusion into the storm. So those are your three things. Let me drop it.