Is there a scientific basis for the folk wisdom that when leaves turn upside down its going to rain?

Question

Is there a scientific basis for the folk wisdom that when leaves turn upside down its going to rain?

Answer 1

I was told by my grandpa, that the leaves on a Cottonwood tree, would turn up (show their white side) when a storm was coming. He told me it was because, the "high" pressure of the storm front, was pushing the leaves up. I don't know if there is any scientific fact to it, but it seems to hold true. I live in the mid west, and when I see the "white side" of a Cottonwood Tree, it usually rains, or at least cools off.

Answer 2

I've not heard that one.  Only thing I can think of is that the humidity increases which in turn causes the leaves not so much to flip over as curl.