Abstract
Clouds were observed forming in the lee of Guadalupe Island under a special sequence of events. One cloud was a narrow, linear cloud, 200 km long, that could not have been advected. Instead, a transparent linear wake was advected downwind. Later, synoptic-scale convergence caused the wake to condense, forming the linear cloud trail. That weak synoptic-scale variation may cause a linear cloud trail and has important implications for understanding ship cloud trails.