Tuesday, August 21, 2012
San Antonio Exceeds the EPA's 3 year 8 hour Ozone Average
San Antonio is now out of compliance with the EPA's National Ambient Air Quality Standard (three year-8hr ozone average) as of today. An early season cool front is to blame for ushering in transported biogenic and anthropogenic pollutants into our area.
The next step for San Antonio will be "negotiating" with the EPA to try and stay out of "Non-Attainment" status. As usual, high ozone events only occur when winds are of the the NE and East in San Antonio during the summer, late spring and fall. As you can see in the graphic below, the two monitors with the highest ozone readings (CAMS 58 and 505) are located on the north side of San Antonio. With winds blowing from the East and NE, that means that local contribution was minimal. Notice that San Marcos and Seguin also had higher than normal ozone readings. Austin lucked out with cloud cover this afternoon and stayed lower than San Antonio's high ozone day.