What causes dangerous tule fog in California’s Central Valley, and why is it becoming less common?

The source of dense tule fog and the factors that are causing people in California’s great Central Valley to see a little less of it.

from California https://www.latimes.com/california/story/2020-01-11/what-causes-dangerous-tule-fog-in-californias-central-valley-and-why-is-it-becoming-less-common
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