Cirrus and Cirrostratus progressively invading the sky are a telltale sign of an approaching warm front. In this case it was an occluded front that was rolling in. It snowed that night.
This community is for pictures and videos of clouds, weather and all sorts of atmospheric phenomena.
Some good links for identifying stuff:
The International Cloud Atlas is a great resource on observing the sky and the weather. The definitive authority on cloud classification.
Atoptics is a more thorough resource on atmospheric optical phenomena.
Rules:
1. Keep it real. Editing images to bring out existing colours and features is allowed. More artistic edits should be marked with [edited] in the title.
2. Mark your original content with [OC] in the title.