San Francisco fog
Fog is a common weather phenomenon in the San Francisco Bay Area and the entire coastline of California extending south to the northwest coast of the Baja California Peninsula. The frequency of fog and low-lying stratus clouds is due to a combination of factors particular to the region that are especially prevalent in the summer. Another type of fog, tule fog, can occur during the winter. There are occasions when both types can coincide in the Bay Area. Some studies suggest that the prevalence of fog in the San Francisco Bay Area has decreased since 1951; however, some suggest these data are insufficient, or even suggest contrary results. Decreases in fog, if occurring, are likely due to climate change and anthropogenic change.
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