This is the 1st movement of the string quartet "Atmospheres." While the cloud forms have a seemingly regular form to them, they are anything but a regular shape. So, using the time signature 19/16, I allow the quartet to move through a variety of different ways of breaking up this irregular time into semi-regular beats creating a sense of movement, while propelling the listener forward.
Genus Cumulonimbus Clouds of the genus cumulonimbus are generally dark grey near the bottom with a flat base. They also rise with extremely high tops. Developing frm Cumulus cloud formations, they occur when the airmass is unstable. Cumulonimbus clouds tend to produce thrunderstorms and are accompanied with strong winds at ground level. The piece is written entirely in 19/16 creating a sense of the instability of their namesake cloud formations. By shifting the way the 16th notes are beamed together, the "pulse" shifts throughout the piece giving the illusion of a regular pattern without ever staying in one place for very long.