Blue spot on the sky

Treeline, originally uploaded by jiihaa.

Houses, originally uploaded by jiihaa.

Curves, originally uploaded by jiihaa.

Snow, originally uploaded by jiihaa.

Today we had cloud cover at night, and the fresh snow reflected the city lights upwards into the clouds. The colors of the clouds were a bit more subdued than sometimes, but there was something I haven't seen previously this winter, a bluish spot of color. I'm not sure where it comes from but it was bright and stayed in place. Here are some photos, all showing the same blue spot on the sky.