Rain and nimbostratus clouds

Nimbostratus clouds are our friendly gray rain clouds. They are low clouds with undulating dark and light masses of soft cloud hanging over our heads.  Nimbostratus form along warm fronts due to the slowly rising air. 


The nimbostratus clouds often have a layer of pannus clouds below them. Pannus is a massed layer of multiple fractus clouds. 


These dark nimbostratus rain clouds covered the sky on Saturday, September 17th for most of the day. It was wonderful to watch them moving and changing shape and color.