Air quality was mostly good today, with some Code Yellow (Moderate) levels in the Southeast (AirNow, top left). There was also Code Purple (Very Unhealthy) in the Pacific Southwest and the Rocky Mountain States, but the source of this elevated PM 2.5 is unknown. However, the PM 2.5 in the Southeast was caused by smoke travelling from Central America towards the US, as seen in NOAA's HMS map, top right. The smoke was light density, so it did not affect the air quality too much. Images of the smoke were captured in NASA's satellite images, bottom left. You can see the smoke mixed in with some cloud coverage.