It’s a nice 69°F outside in NorCal but the air quality is gnarly because of agriculture/large property owner pile burning. #CaWxThis image displays a PM2.5 Air Quality Index (AQI) reading with two channels: Channel A at 143 and Channel B at 138. Below the readings is a PM2.5 AQI history bar graph, showing varying colors from green (better air) to red.