RENO, Nev. (AP) - Increased smoke from California wildfires has put northern Nevada's air in the unhealthful range again, health officials said Thursday.
Children and people with respiratory problems were advised to stay indoors in the Reno, Carson City and Minden areas along the eastern Sierra.
The National Weather Service issued an "air stagnation alert" for much of the Sierra and western Nevada, including the Reno-Lake Tahoe area.
Pollution and smoke might increase to dangerous levels until the alert expires at noon Friday, according to the weather service.
Visibilities will drop to below a mile in the Sierra at times, and below three miles in western Nevada valleys, the weather service added.
Tracie Douglas, spokeswoman for the Washoe District Health Department, said deteriorating air quality could trigger a Stage 2 pollution alert by Friday in Reno.
That would put air quality in the "very unhealthful" range and result in a recommendation that all residents stay indoors, she said.
A Stage 2 alert was issued June 25 in Reno, the first such alert that Douglas could recall in her 21 years with the department.
"The biggest problem is we have no control strategies for this," she said. "In winter, we do have control strategies such as bans on using woodstoves. At this point, this is Mother Nature and there's not a thing we can do."
Air quality has been in the unhealthful range off and on in the Reno-Tahoe area since lightning touched off hundreds of wildfires in California more than two weeks ago.
The blazes have burned nearly 1,100 square miles and destroyed nearly 100 homes. Some 1,460 fires had been contained, but more than 320 were still active Thursday, authorities said.
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