FRESNO, Calif. (KSEE) — Some in the Central Valley noticed diminished air quality Thursday morning after a plume of smoke rising from the KNP Complex actually folded over and dipped into the Valley.
The event spiked air pollution levels to rare extremes even for fire seasons, experts say.
Daytime and nighttime temperature changes helped sink a thick column of wildfire smoke directly into the center of the Valley overnight. High pressure allowed the smoke to stay highly concentrated, and for a brief time made conditions in Fresno similar to places right next to the fire.
All around, air quality monitoring stations reported level five — the highest category of fine particulate pollution.
Heather Heinks at the Valley Air District says although monitoring provides the best picture, they don’t always show everything.
“Smoke does travel in plumes and it may have moved through a neighborhood and not have hit wherever that monitor location is,” Heinks explains.
When fine particulate pollution reaches this highest level medical evidence shows even short exposures may be harmful.
“Research definitely shows it has adverse impacts to your health. It’s going to initially aggravate any condition that already exists,” Heinks says. “COPD, any kind of respiratory condition, COVID, asthma, bronchitis, all of those conditions. Those folks will know when it is unhealthy for sensitive groups outside long before the monitor alert maybe came on their phone because they are already struggling to breathe.”
At level five school recess takes place indoors and many athletic events are canceled. But levels are constantly changing. Particulate matter concentrations in most of these locations fell out of level five by early afternoon.
“Rely on your senses,” says Heinks. “If you are smelling that smoke, that is an indication you are breathing in fine particulate matter and it is going to impact your health.”