High PM2.5 concentrations continue to be reported along the western coast of the United States, with Code Yellow and Orange AQI levels reported over California (Airnow animation). Oregon and Washington reported only Code Yellow PM2.5 AQI levels. Today's weather over the west coast didn't aid in the ventilation of pollutants from within the boundary layer. A high pressure system (top right image) over this region produced stagnant conditions (low winds) that didn't disperse any organic particulate that might have been injected in the boundary layer from burning-heating conditions.
AOD readings from MODIS-Aqua suggest a slight improvement in the air quality over California. Light haze/smoke was still visible in the MODIS Aqua rgb image over northern California. NO2 concentrations from OMI are high near San Francisco, and no correlation with the AOD values, suggesting that the particles maybe of organic origin.