Utah air quality among worst in world as cold front brings smoke from Western fires

SALT LAKE CITY — Utah's air quality already took a hit this week as smoke from Western wildfires returned to the state, but the air quality across Utah worsened Friday — even to levels considered worst in the world — as a cold front sweeps heavier smoke from those fires into the Beehive State.

Christine Kruse, the lead meteorologist for the National Weather Service's Salt Lake City office, said the cold front moving from the west has picked up smoke from fires in California and Oregon, including the growing Dixie Fire that leveled a small California town earlier this week. The cold front carried heavy smoke concentrations as it moved east through Nevada Thursday.

It then reached the Wasatch Front Friday morning and was crossing through the rest of the state.

"What that will do is it will bring that area of smoke right into Utah," she said. "We have some models that try to forecast smoke concentration both at the surface and through the whole column of the atmosphere, and all of that model data is showing very, very high concentrations of smoke as that cold front moves through and then behind the cold front."

Impact on air quality

KSL Air Quality showed air quality levels reaching "red" status throughout the Wasatch Front as the smoke came in. It got so bad that WorldIQ Air, which tracks air quality across dozens of cities globally, said Salt Lake City's air quality became among the worst in the world as soon as sensors picked up the heavy smoke levels.

The Utah Department of Environmental Quality's Division of Air Quality originally forecast air quality to reach levels unhealthy for all groups of people in Salt Lake County; however, the department said later it adjusted that to include all of Davis, Tooele and Utah counties, too.

"Pollution concentrations are such that we recommend even those not in sensitive populations avoid outdoor activity as much as possible today," it tweeted.

Most other places in the state were forecast to have levels unhealthy for people with health conditions that make them sensitive to smoke. That includes people who have a heart or lung condition, such as asthma, as well as young children, adults 65 or older and pregnant women. People in those categories should "reduce or better yet avoid prolonged or heavy exertion outside" because of the air quality, according to the Utah Department of Environmental Quality.

Dr. Denitza Blagev, a pulmonary physician at Intermountain Healthcare, echoed those recommendations. She advises Utahns to reassess any plans to go outdoors, especially those venturing into the outdoors for walks, hikes and bike rides while air quality is poor, adding that smoke from fires does appear in high-elevation areas of the state unlike wintertime inversion events.

Blagev also called Friday's smoke the worst air quality event the state's seen this year, virtually appearing out of nowhere for those who weren't aware of the forecast.

"I think one of the surprising things was just how quickly it changed from this morning, when air quality was really in the 'green' in terms of (particulate matter)," she said. "And when I when I last looked, the air quality index was 164 — really unhealthy for anyone, not just children, not just older people, not just sensitive groups."

Poor air quality and exposure to it, she added, is linked to spikes in multiple health issues, such as pneumonia, bronchitis, heart attacks and stroke. It also increases the risk of viral infections, such as COVID-19. That's why she said it was "really unfortunate" that the poor air quality arrived in Utah as the number of new COVID-19 cases caused by the delta variant continues to rise.

A University of California-San Diego study published earlier this year found that respiratory hospitalizations increase upwards to 10% when particulate matter from wildfire-specific events occur, compared to a high of 1.3% when there are higher counts of particulate matter not tied to wildfire smoke.

University of Utah researchers published a study this year that found wildfire smoke can seep indoors easier than other forms of particulate matter. Still, the Salt Lake County Health Department recommends people purchase an indoor air purifier and run on the highest setting during a high wildfire smoke event.

The agency also recommends that people avoid going outside and that they keep their windows and doors closed as much as possible, as well as limiting any use of swamp coolers and close off fresh air intake vents on window AC units. They, along with state environmental officials, advised Utahns to drive less or "chain" trips to reduce driving to help lessen other sources during a bad air quality event.

For those who go outside, Blagev said, N95 masks — something that people may have on hand to thwart the spread of COVID-19 — work well during high pollution events in addition to stopping the spread of COVID-19. Homemade and other forms of masks don't have the same level of effectiveness when it comes to wildfire smoke, she added.

Cox on smoke: 'Good time to stay indoors'

Meanwhile, many Utahns turned to social media Friday to react as the wall of smoke made its way into Utah, including Gov. Spencer Cox.

"I don't ever remember smoke from other states coming in so thick to Utah," he tweeted Friday. "We've been watching it for a couple days and now it's here. A good time to stay inside for those with sensitive health conditions."

Multiple government agencies and fire departments urged residents to not report the smoke to emergency services because there weren't any active fires in the area.

"Please refrain from reporting a fire unless you see a defined column of smoke or flames," Summit County officials tweeted.

Utah Fire Info, which is composed of federal and state firefighting agencies, added that the heavy smoke "will be hard to identify" new fire starts in Utah. They added that is why it's "extremely important to use Fire Sense and recreate responsibly."

Officials with the Salt Lake City International Airport said flights from the airport weren't impacted by the smoke but there could be flight delays if the smoke thickens. The heavy smoke did, however, force several high schools to cancel athletics practices.

Brighton, Maple Mountain, Mountain View and Provo were some of the high schools that announced they had canceled or rescheduled football intrasquad events originally slated for Friday. And the Canyons School District canceled all outdoor extracurricular activities, sports events and practices Friday as well.

"We hope to resume activities over the weekend, but will keep an eye on the air quality and notify families of any future cancellations," said Kristen Stewart from the district's communications office.

University of Utah Athletic Director Mark Harlan told ESPN 700 that University of Utah athletes also left practices early due to the air quality.

How long will it last?

The weather service anticipates that the heaviest smoke concentrations will occur when the cold front passes through and a few hours after. It will dissipate some but will still be strong enough that it can block some visibility after that.

"Like, if you can look across the (Salt Lake) Valley at, say, the Wasatch (Mountains), you'll not be able to see the Wasatch," Kruse said. "That kind of smoke."

The level of smoke is expected to linger in Utah through at least Saturday and, maybe into Sunday, Kruse added. The Great Basin Coordination Center forecast "significant" smoke impacts for most of Utah through at least Sunday.

Current air quality reports for areas across the Wasatch Front, as well as stations in northern, eastern and southern Utah, can be found at the KSL Air Quality Network.

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