Description: Image shows the hourly-averaged concentration of particulate matter of fine particles with diameters less than 2.5 micrometers (PM2.5) over the western contiguous U.S. during the last 31 days. Forecast hours are shown along the x-axis. The gray dashed line is the observed mean, while the solid black line and solid red line are the raw AQM forecast and the bias-corrected AQM forecast from 12Z runs, respectively. The closer that the forecast mean value is to the observed mean value, the more accurate the PM2.5 forecast was.



Description: Similar to the first image, except for the central contiguous U.S. during the last 31 days.



Description: Similar to the first image, except for the eastern contiguous U.S. during the last 31 days.



Description: Similar to the first image, except for the southern contiguous U.S. during the last 31 days.