Morning has broken - though shade keeps the frost alive

So spring is officially here.  Lovely morning for it.  There's frost on the roof of the building downhill from me again.

Some trees are casting shade and the sun doesn't seem to be doing the melting line like it did a few days ago. (Here.)

Oh there it is, where the higher roof shades the lower one, and the frost melts back as the sun hits it.

Isn't it nice with all the word's trauma and news that I can focus on how the sun melts frost on a neighbor's roof?