Business was brisk at Teddy's Cocina in Pasadena as wildfire evacuees ate lunch and passersby ducked indoors to escape from the brown, smoky air blanketing the city.

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.

Smoke from the raging Southern California wildfires is filling city skylines, causing officials to warn residents of poor air quality.