Virtually all of Los Angeles is experiencing "unhealthy" air quality levels amid the devastating fires that ignited in early January.

The smoke was expected to most heavily affect northwest coastal LA County, and in areas nearest the Palisades, Eaton and Hurst wildfires.

AirNow is a collaborative effort of federal agencies that provides air quality data across the U.S. The site also has up-to-date information about the wildfires, resources, data, and interactive maps to help users learn more about particular areas and how they might be affected. There's also a free AirNow mobile app.