Kings Canyon wildfire blamed for smoke over Las Vegas

Wildfires are burning all around Southern Nevada, including northern Arizona.

But the blaze that has brought dense smoke to the Las Vegas Valley over the past three days is the Rough Fire, which was ignited July 31 by a lightning strike in Kings Canyon in the southern Sierra Nevada, east of Fresno, Calif.

As of Saturday morning, Southern California Public Radio reported that more than 1,600 firefighters have been battling the Rough Fire, which remained only 3 percent contained and has engulfed close to 42,000 acres.

Air quality levels across Las Vegas, however, are expected to improve in the days to come and in September unless wildfires continue to rage in the Sierra.

"On Wednesday and Thursday it was smoky no matter where you were," said National Weather Service meteorologist Chris Stachelski. "You couldn't even see Mount Charleston."

Stachelski said southwest winds have started to clear the air in the valley since then.

"Most of the smoke is pretty much gone," he said. "There is some residual smoke to the north, which will take a little more time to push out, but I don't anticipate any more coming in."

The morning is typically the smokiest time of day, Stachelski said.

"Winds are usually lighter in the morning so smoke tends to drop down and fill in so you'll see more haze," he said. "In the afternoon the winds pick up and it helps clear out the smoke and haze."

Clark County Air Quality Monitoring Manager Phillip Wiker said that in addition to the Rough Fire, the Cabin Fire, which began mid-July in Los Angeles County, Calif., also brought smoke into Southern Nevada.

The Cabin Fire burned nearly 7,000 acres and was 96 percent contained as of Friday, Southern California Public Radio reported.

Wiker added that the Walker Fire farther north in Mono County, Calif., which burned almost 4,000 acres since Aug. 14 and was 50 percent contained as of Friday, could also bring hazy conditions to Las Vegas.

So far this summer Las Vegas has experienced several incidents that produced hazy conditions.

According to Wiker, the Clark County Department of Air Quality monitored smoke from a June 18 fire in San Bernardino, Calif., fireworks from July 4 celebrations, and the Willow Creek fire in Fresno at the end of July.

He said the air quality for ozone levels for the remainder of the summer should be moderate with the potential of one or two days being unhealthy for sensitive groups such as the young and elderly.

"We should be good for the rest of August but it does get more sporadic in September with more good days than moderate," he said. "Air quality in September usually improves — providing we don't get wildfires."

If wildfires do continue to burn, Dr. Nancy Williams, a medical epidemiologist for the Southern Nevada Health District, said because smoke contains tiny particles, it can inhibit oxygen getting into the circulatory system when it's inhaled.

She said young children, pregnant women and the elderly as well as diabetics and those with lung and cardiovascular conditions are especially at risk of smoke damaging their bodies.

"Stay indoors, keep windows and doors closed and use air conditioning instead of opening windows, and the same goes for when you're in the car," she said. "Those who don't have air conditioning should find another place to stay if the smoke in the air is significant."

Reducing physical exertion such as running and playing tennis outdoors is also recommended.

"If you're wheezing, have a persistent cough, chest pain or feel overwhelmingly fatigued, it's time to call 911," Williams said. "Don't do things that make you breathe harder, and keep yourself away from the smoke."

No air quality alert was issued for Saturday, although the county was under an air quality advisory until Friday evening.

"It will remain hazy up north for a little while longer but I don't see any new windows for smoke to move in," Stachelski said. "As the winds continue to move south, we'll definitely see improvement."

Contact Ann Friedman at afriedman@reviewjournal.com or 702-380-4588. Find her on Twitter: @AnnFriedmanRJ