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Funny you should mention "hot, dry, things burn". I once did a little digging into the matter, and it turns out that once ignition temperature is reached, the difference between a fresh green leaf igniting vs. a dry brown one is on the order of just a few seconds, maybe just one or two. Which is surprisingly fast, but not so surprising when you realize that advancing flame fronts may be in the high hundreds to low thousands of degrees - plenty hot enough to quickly desiccate even the freshest leaf. It turns out that bigger factors are the size and shape of the leaf in question, what type of plant it is, and of course what the winds are doing.

Physical wetness, though, may make quite a bit of difference, especially when it comes to a fire actually igniting to begin with. But even that may not matter so much when it comes to things like lightning strikes, which may be in the tens of thousands of degrees.

So, for example, if the temperature might normally be 70F but instead is closer to 100F, that small difference is minimal compared to the temperature of any flames. But it might make a huge difference to someone fighting those flames, unless maybe they are right in the thick of them.




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