Weak Emergence Is the Uncontroversial Kind

There's a sense in which it's obviously true that there are emergent phenomena. But the weak emergence says all of that is fixed, in some sense, determined by the underlying most fundamental dynamics in our world. Why isn't everything like a hurricane out of raindrops impossible to predict no larger structure? Do we understand that? I'm almost thinking it's a question for a mathematician or a physicist who wears dual hats as a mathematician.