Frost on the skylight, and the pearly dawn breaking. Now it's turned into blue skies and raking sunlight.
As a child in winter-whitened Quebec and even in the balmy Lower Fraser Valley, BC, and again as an adult in Halifax, NS, living in a house without heating in the bedrooms, I often encountered ice crystals on the inside of the windowpane. Often? Not really all that often, not getting-dressed-under-the-bedclothes often - but often enough ... hurrah for central heating!