Here is a message for Boise residents who are sick of the omnipresent smoke in the air this summer: Be glad you don’t live in Salmon. It hasn’t been so swell in Ketchum either.

The Boise area is surrounded by wildfires and keeps getting smoke pumped in from blazes burning in California and Oregon during the day. More smoke leaks down into the Valley overnight from the massive fires near Stanley, Featherville and Salmon.

The Idaho Department of Environmental Quality has issued a yellow air quality alert for Boise Friday, which means air quality is expected to be in the moderate range. The Valley has had 39 days of moderate or poorer air quality since June 1, including 21 days in August.

Wildfire smoke impacts aren’t uncommon in Southwest Idaho, but they are rarely so prolonged.

“Looking over the air quality data for the past 10 years, this summer, especially the month of August, has been one of the worst air quality periods on record with regards to smoke impacts,” Michael Toole, a regional airshed coordinator for Idaho Department of Environmental Quality, said Thursday.

As bad as things have been in the Boise area, they could be worse.

Salmon, which is close to Idaho’s largest wildfire, had a purple air quality alert on Thursday — representing the worst air quality day in Idaho this year, DEQ officials said.

“Salmon is just getting hammered from the smoke from those fires,” Toole said of the 196,000-acre Mustang Complex Fire.

PURPLE HAZE

Most of Boise’s air quality alerts are yellow or orange, two or three steps down the quality scale from purple on the Department of Environmental Quality’s six-step color scheme to inform the public about diminished air quality.

The colors are: green (good), yellow (moderate), orange (unhealthy for sensitive groups), red (unhealthy), purple (very unhealthy), and maroon (hazardous).

Air quality index, or AQI, numbers provide the basis for the color scheme. An AQI forecast below 50 is considered good, while 51 to 100 triggers a yellow alert.

Boise has had 31 days in the yellow range this summer and seven days in the orange, which means an AQI of 101-150. The highest was on Aug. 12, when an AQI of 157 was recorded — that’s in the red zone.

The AQI at Salmon at noon Thursday was 208.

“The smoke was so bad (Thursday) we told our guests we couldn’t do their float trip today for safety reasons,” said Cathy Kranney, who works at Rawhide Outfitters in Salmon. “There is just so much smoke in the air ... All we need is a good rain.”

NO END IN SIGHT

Kranney shouldn’t get her hopes up. Weather forecasts don’t show any evidence of what fire officials like to call “a season-ending event” happening anytime soon.

That event is when a series of wet and cool weather systems start moving across the Pacific Northwest and Rocky Mountain states and bring cooler temperatures, lots of rain and not so much lightning.

Officials at the National Interagency Fire Center in Boise said Thursday long-term weather forecasts for September show no evidence of such an event occurring. There might be some rainstorms, but not the kind that might help stomp out the Trinity Ridge, Halstead and Mustang fires, which have burned about 450,000 acres of forestlands across the state since late July.

Expect smoke to hang around the Boise area for the forseeable future as well. National Weather Service forecasts for the next 10 days don’t show much change. Expect sun and smoke, with possible brief respite on Saturday if northwest winds blow through Boise. Forecasts predict less rain than usual for the next month, meteorologist Valerie Mills said.

Patrick Orr: 377-6219, Twitter: @IDS_Orr