Temperatures around 100 degrees are in the forecast for southwest Oregon over Labor Day weekend.

The National Weather Service Monday issued a heat advisory through 11 p.m. Tuesday because of the forecast, which comes in spite of the curtain of smoke that can act as a shield from the heat.

“The combination of heat and smoke is a problem for the people outside, especially the people who have to work outside, and for sensitive groups," said meteorologist Connie Clarstrom. "It can really trigger health problems much quicker than if you had only smoke or only heat."

Children and the elderly are especially at risk during such a one-two punch, as they are more susceptible to the effects of both heat-related illnesses and diminished air quality, said Dr. Jim Shames, Jackson County Health & Human Services medical director.

"The problem is that for certain individuals, both of those conditions compromise," Shames said. "If you combine them together, in a fairly short period of time they could have their health impacted."

Healthy individuals aren't necessarily spared either if they push themselves too hard or too long in the smoky, roasting air, he added.

Temperatures between the mid- and low-90s are forecast across Jackson County through Thursday, with nighttime lows as high as 70 degrees. Triple digits are expected Labor Day weekend, weather officials said.

That's in tandem with air quality that hasn't been at "good" levels since Aug. 13, according to data from the Oregon Department of Environmental Quality's Air Quality Index. On Monday, all but one of the eight air-quality stations that monitor fine particulate matter from wildfire smoke in Jackson, Josephine, Klamath and Douglas counties registered "unhealthy" air quality.

Fires

The smoke continues to drift in from multiple fires spread across several counties, including the Miller Complex, Chetco Bar fire, High Cascades Complex and multiple fires burning across western Siskiyou County.

The Miller Complex, made up of 25 lightning-sparked fires in the Applegate Valley, was listed Monday as 9,628 acres in size. Fire officials previously had sized the fire at more than 14,000 acres but reduced their estimate due to a computing error. While all 25 fires continue to be monitored, only six of the fires are growing: Creedence fire, Bigelow fire, Burnt Peak fire, Seattle fire, Abney fire and Cook fire.

A Level 1 — "get ready" — evacuation advisory was issued along parts of Upper Applegate Road, including Palmer Creek Road at Upper Applegate Road to the split of U.S. Forest Service roads 1090 and 1095; west of Upper Applegate Lake and east of the Applegate River from Palmer Creek Road to Jackson Campground; Boulder City at 11425 Upper Applegate Road, Carberry Creek Road at Applegate Road to Steamboat Ranch, and the Joe Bar area.

An estimated 550 personnel are assigned to the complex.

The Chetco Bar fire, a lightning-sparked blaze burning in the Kalmiopsis wilderness, had grown to 107,993 acres Monday. Numerous homes nearby have received Level 1, 2 and 3 evacuation notices, with officials continuing to update an interactive map showing areas under specific advisories. That map is available to view online at https://goo.gl/keU1PZ.

On Sunday, the flames continued to push in multiple directions, including northwest toward Hog Mountain, north toward the Snow Camp trailhead and south to above Emily Creek. More than 1,500 personnel are working on the fire, which has no containment.

Recent movement on the Blanket Creek fire, one of three large fires burning in the High Cascades Complex near Crater Lake, prompted a Level 1 evacuation advisory for Mazama Village over the weekend. The advisory does not affect Rim Village, park headquarters or other areas of the park. The complex, made up of the 9,299-acre Blanket Creek, 5,625-acre Spruce Lake, and 3,314-acre Broken Lookout fires, is 44 percent contained, a downgrade from recent 60 percent containment estimates. 

The following trails in Crater Lake National Park remain closed:


Pacific Crest Trail, from the park boundary to Highway 62 and from the intersection of Dutton Creek Trail north to the North Entrance Road
Boundary Springs Trail
Bald Crater Loop Trail
Bert Creek Trail
Lightning Springs Trail
Union Peak Trail
Stuart Falls Trail
Pumice Flat Trail

— Reach reporter Ryan Pfeil at 541-776-4468 or rpfeil@mailtribune.com. Follow him at www.twitter.com/ryanpfeil.