The Catalina Eddy

Image: NASA Earth Observatory

On June 13, 2018, the National Weather Service reported a small but well-defined eddy off the coast near the border of Orange County and San Diego County. An eddy is a counter-clockwise circulation pattern of fog and clouds. The Catalina eddy typically brings cool, moist air to the coast. A similar eddy was also reported in 2013 (pictured) by the NASA Earth Observatory.

Why do the clouds take on a whirlpool shape? What causes the Catalina eddy, and when does it typically appear?

Resources:

NASA Earth Observatory: Catalina eddy

San Diego Union Tribune: The beauty of a Catalina eddy

Times of San Diego: Catalina eddy phenomenon spotted off San Diego coast