California Wildfires: Why the smoke is sitting over the Bay Area

SAN FRANCISCO (KGO) -- Our seventh consecutive day of breathing unhealthy air will become our eighth on Friday. And if you think it's become worse over the last few days in the Bay Area, you may be right. Here's why smoke from Butte County's Camp Fire is sitting over the region and not budging.

High pressure to our west keeps steering smoke from the Camp Fire across our neighborhoods. Sinking air within high pressure also puts a lid on atmosphere and concentrates all the smoke near the Earth's surface.

MAP: Current Bay Area Air Quality Conditions

Forecast models hint at a wind shift starting Saturday. But while winds blowing more from the east and southeast will help improve the air quality they'll never completely clear our sky.

A Winter Spare the Air Alert is in effect through Tuesday. The focus will be more on "unhealthy air for sensitive groups" as opposed to our current air which is "unhealthy" to "very unhealthy" for everybody.

An onshore wind begins Wednesday and so does our transition to completely healthy air. Rain and our cleanest air should arrive Thanksgiving Day. Now that's something to be thankful for.

See more stories, photos and videos on the Camp Fire in Butte County here.