U.S. Air Quality

Good Air Quality in U.S.; Fires in Central America Continue

Tuesday was a relatively uneventful day for air quality in the U.S., with Code Green (Good) air quality across most of the nation. The 24-hour average PM2.5 AQI values (below on left) and 8-hour average ozone maximum AQI values (below on right) from AIRNow both show only a few scattered areas of Code Yellow (Moderate) conditions across the country.

Two large weather systems helped to keep air quality in the Good range. Tuesday’s MODIS Terra true color image for the continuous United States from IDEA (below on upper left) indicates the cloud cover over the eastern and western coasts associated with the low pressure systems, and a clear region in the Mid-West due to high pressure. The corresponding MODIS Terra AOD image from IDEA (below on upper right) shows a few areas of slightly elevated AOD, possibly due to fire activity across the central portion of the nation. Today’s NOAA Hazard Mapping System (HMS) Fire and Smoke Product (below on bottom left) illustrates the many fires burning across the mid-section of the country. Fortunately, these fires do not appear to be significantly impacting surface air quality in the Mid-West. HMS also shows that the real story continues to be the seasonal fires in Central America. Large numbers of fires are still burning across the region, with the highest concentration of fires and smoke located in the Yucatan peninsula, Guatemala, Belize, Honduras, Nicaragua, and Panama. Thick smoke from these fires is visible over the Yucatan, Guatemala, and Belize in today’s MODIS Terra true color image from NASA MODIS Rapid Response (below on bottom right in Google Earth). Due to the shifting weather patterns, smoke from the Central American fires does not appear to be impacting surface air quality along the Gulf of Mexico today.