They may have been gazing out the car window during a road trip, or tanning on the beach, or on a morning ... which look like a pattern of ocean waves in the sky. Kelvin-Helmholtz clouds, also ...

The biggest threat in coming days will come from the Pacific Ocean, rather than from the sky. A Beach Hazards Statement warns of a moderate to high risk of sneaker waves between 9 a.m. and 9 p.m ...