San Joaquin Valley Air Pollution Control District warns that air quality is expected to deteriorate in parts of the Valley over the weekend as temperatures rise to record levels. Air pollution officials caution Valley residents to reduce exposure to ozone and particulate matter (PM) emissions by remaining indoors if possible.

High pressure is continuing to build over the San Joaquin Valley, raising temperatures and increasing ozone and PM levels in the Valley. That pressure acts as a “lid” over the bowl of the Valley and traps pollution. Additionally, dry conditions on the Valley floor and in the foothill and mountain areas bring an increased risk of wildfires and the potential for additional air quality impacts from wildfire smoke.

High ozone and PM pollution can trigger asthma attacks, aggravate chronic bronchitis, and increase the risk of heart attack and stroke. Individuals with heart or lung disease should follow their doctors’ advice for dealing with episodes of PM exposure. Those with existing respiratory conditions, including COVID-19, young children and the elderly, are especially susceptible to the health effects from this form of pollution. Anyone experiencing poor air quality due to wildfire smoke should move indoors, to a filtered, air-conditioned environment with windows closed. The common cloth and paper masks individuals are wearing due to COVID-19 concerns may not protect them from wildfire smoke.

Residents can use the District’s Real-time Air Advisory Network (RAAN) to track air quality at Valley locations by visiting myRAAN.com. The public can also check the District’s wildfire page at www.valleyair.org/wildfires for information about any current and recently past wildfires affecting the Valley. In addition, anyone can follow air quality conditions by downloading the free “Valley Air” app on their mobile device.

For more information, visit www.valleyair.org or call the District office in Modesto at 209-557-6400.