This is what can happen after a heavy snowfall if my porch and arbor out front are undisturbed for a day or two. The snow falls normally and stacks straight up, then in the right weather conditions, stacked snow partially melts in such a way that it slumps over but doesn't fall. This time it was particularly interesting on my porch because the slump changes directions halfway across the railing.
It reminds me of that painting with the melting clocks.
