Valley officials warn of worsening air quality as triple-digit heat arrives

Updated 2 hours ago
FRESNO, Calif. (KFSN) -- Air quality officials are urging Central Valley residents to take precautions as a stretch of triple-digit temperatures is expected to bring increased levels of air pollution and other health risks.

Hazy skies have already settled over the region, and the San Joaquin Valley Air Pollution Control District says the hottest part of the day can often be the most dangerous when it comes to air quality.

"It is summertime in the San Joaquin Valley, which means we can expect heat. What do you think about when you're thinking about heat? Well, definitely air quality," said Heather Heinks of the air district.

Officials say air quality conditions have generally been favorable so far this year, but the current heat wave could present a significant challenge.

"We're concerned about ozone pollution. It's basically mixing the things that get produced at ground level; they turn into ozone when the sun is hot. So you can imagine 2, 3, 4 o'clock in the afternoon, it's going to be at its highest," Heinks said.



In addition to rising ozone levels, experts say agricultural activity could contribute to poorer air quality. Farmers may take advantage of dry conditions to disc fields and remove crop residue, a process that can stir up dust and other airborne particles.

"Not only the air pollution is high, the smog level is high, but when you disturb the dirt, that could give you additional pollutants in your lungs," said Dr. A.M. Aminian.

Forecasters are also monitoring the possibility of monsoonal moisture moving into the region later in the weekend, bringing increased humidity and the potential for thunderstorms.

The air district said cloud cover associated with those conditions could help limit ozone formation.

"It might bring lightning strikes, but it also might bring cloud cover. That cloud cover could prevent ozone from really getting too bad," Heinks said.



However, Aminian warned that higher humidity can create additional health concerns during periods of extreme heat.

"When it goes down, again deprives you from getting enough oxygen that your body needs, and that can make it easier to go to the advanced stage of the heat stroke," Aminian said.

Officials are encouraging residents, particularly those with pre-existing health conditions, to stay hydrated, limit time outdoors during the hottest portions of the day and monitor local air quality conditions as the heat wave continues.

Current air quality information and weather forecasts are available on ABC30.com.

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