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Name: Vicki
Status: Educator
Age: 40s
Location: N/A
Country: N/A
Date: N/A 

What are the dynamics behind the night and morning low clouds seen along the southern California coast?
I understand that the sea breeze advects moisture inland, but why this particular stratus pattern and why an intensification around the summer solstice (our June gloom)?
How does this local weather pattern relate to the Pacific anticyclone?


Your greatest period of cloudiness is winter through early June, mostly a result of the effects of the California current, which begins close to the central Pacific Ocean and flows NE and then north along the southern California coast. Cool air is advected, mixed, and lifted just enough to produce shallow stratus and stratocumulus clouds along the extent of the current. The Pacific anticyclone appears to play a minor part. These clouds back off of the mainland in the daytime as the air over the land warms and expands (more of less pushing air, and the clouds, offshore). At night, the air over the land cools and the clouds can spread back over the land.

David cook

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