Small but regular ripples of thin white clouds are unique to cirrocumulus, which often occur with other cloud types at higher levels. They are most often found with larger-scale weather systems. A small or isolated cirrocumulus clouds is not especially important. Several patches or a widespread layer may indicate increasing moisture or instability ahead of an advancing weather system. Silhouetted below the cirrocumulus in this photo is the Mesa Laboratory of the National Center for Atmospheric Research in Boulder, Colorado.
Courtesy of UCAR Digital Image Library