The leaves of deciduous trees, like maples and poplars, do often to turn upward before heavy rain. The leaves are actually reacting to the sudden increase in humidity that usually precedes a storm. Leaves with soft stems can become limp in response to abrupt changes in humidity, allowing the wind to flip them over.

Do trees know when it's going to rain?

Tree Leaves Can't Predict a Storm. While it would be super cool if they could, trees only react to the weather around them. You'll have to stick to your crystal ball (or weather app!) to see when a storm is coming.

How do you tell if it's about to rain?

Look at the shape of the clouds.

The types of clouds in the sky can tell you a lot about the weather. In general, clouds that are white and high indicate good weather, and clouds that are dark and low mean rain or storms are on the way. White, wispy clouds usually mean that the weather will be clear.