AUSTIN, Texas — As temperatures rise, air quality is falling.
On Wednesday, the National Weather Service issued an Air Quality Alert due to an expected peak in ozone for Central Texas.
This alert spans all day for Williamson, Travis, Caldwell Hays, and Bastrop Counties, and a similar alert may be issued again on Thursday, as the forecast remains hot, dry and calm.
Current air quality thresholds for Austin on Wednesday are dipping into the "unhealthy for sensitive groups" category. Further east toward Houston, air quality values are even lower.
The main pollutant on Wednesday is ozone.
"People with lung disease such as asthma, children and teens, older adults, and people who are routinely active outdoors for six or more hours a day: Reduce your exposure by choosing less strenuous activities or shortening the amount of time you are active outdoors," the U.S. Air Quality Index website reads.
While ozone is in the atmosphere on any given day, hot and calm conditions can increase air pollution problems. Strong UV rays and heat cause nitrogen oxides and organic compounds, which are produced by things like car exhaust, to come together and generate ozone.
On days with strong high pressure (sinking air), like Wednesday, the additional ozone that gets produced is then trapped closer to the surface, which in turn, decreases air quality.
Similar conditions on Thursday may call for another Air Quality Alert, but as we near the end of the week, air quality conditions are expected to improve.
