This afternoon’s rather strong northwest winds created optimal conditions for orographic cloud formation over North Table Mountain. Winds were entering the image from the left and hitting N. Table, forcing the air upward. The rising air cooled (from expansion) to below the dew point, causing the increasing cloud layer running toward the south (from left to right in the picture). In the summer, such orographic uplift can be responsible for spawning thunderstorms as the unstable clouds continue to rise after the initial push upwards.
This TerraLapse composite image represents 7 minutes, 28 seconds of cloud development: