A while ago, it had snowed. Then, when the weather got warmer, the snow melted, except for a few places in the shade or where there were bigger piles.
And then for several days, temperatures were always around freezing, so it was really funny: the little patches of snow remained where they were, only melting a little, if at all, so you'd have a little patch here and a little patch there in seemingly-random places, with nothing in between.
Today, that was over: it snowed quite a bit and now everything is covered with snow again :p