Dear Lazyweb

It's very foggy here at the moment, and just next to the trees in front of our house (and elsewhere, although it's particularly noticeable in front of our house because there's no road noise) there's a really cool rainy-crackling kind of sound. I can't quite tell whether it's leaves freezing, water condensing inside the bark and forcing the bark to expand, water condensing onto the leaves and dropping as a sort of localised rainstorm, or something else. Does anyone know the answer?