Posts Tagged ‘lenticularis’

Classic clouds #3 – altocumulus lenticularis

December 23, 2011

Well, there’s a bit of a buzz about lenticular clouds at the moment as there were some wonderful photos taken of a lenticular cloud in West Yorkshire yesterday.

Lenticular cloud in West Yorkshire on 22/12/2011. Photo from Paul Hudson's blog.

These crisp and layered lenticular cloud are relatively rare in the UK as they form downwind of mountains or hills.

What happens is that the air flowing over the hill gets “knocked” upwards which results in a type of wave forming. The cloud forms on this wave at a point where the flowing air moves upwards and cools to a point where the water vapour condenses into a cloud. So, although the cloud is stationary, there is a constant flow of air going through it.

Quick sketch of lenticular cloud formation.