Video taken in Laguna Beach Wednesday night shows the spectacular sight.
The footage was sent to Eyewitness News by viewers Mark Girardeau and Patrick Coyne.
The glowing blue hue is from bioluminescence, a semi-regular occurrence, when tiny organisms such as plankton get stirred up and give off this light.
We saw a lot of it last spring, up and down the coast. But it's hard to predict, so we can't say if this year will be the same.
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