Will this sentence be used improperly?

Clouds are like signs of chaotic weather. You can judge the weather by observing them.

It's confusing. Why is this word inappropriate?

That should be right.

There is nothing wrong with the confusing description of the weather. It is changeable and unpredictable. If the original sentence is changed to: "clouds are like signs that confuse the weather, unpredictable and dazzling." So there is no problem. It is wrong to confuse the context of this word in your example, because what you want to embody and emphasize is that clouds can identify weather changes. The first half of the sentence is confusing and unpredictable, and the second half says that clouds can know the weather, which creates a contradictory context!