The haze in the hills that wreathe the Rogue Valley is primarily from pollutants such as car exhaust and smoke from wood stoves and prescribed burns trapped by an inversion, and not from wildfire smoke, weather officials said.
The last three days have seen “pretty strong” inversions, meteorologist Shad Keene said, citing a 20-degree average temperature difference between the surface and about 1,000 feet above the ground.
“None of the pollutants that we’re generating here in the valley are leaving,” Keene said.
That said, area air quality has mostly stayed put in the “good” category so far this month — with a few dips into the “moderate” category recorded at the Grants Pass, Cave Junction, Medford, and Ashland stations — according to Oregon Department of Environmental Quality data.
The spell of dry weather is expected to continue the rest of the week. A possible wind shift on Sunday could deal a blow to area air quality, though that all depends on how much smoke the Klondike Fire, burning northwest of Selma in Josephine County, is producing by that point.
“If the Klondike was producing a lot of smoke at that time, it could shift over into the valley,” Keene said.
The Klondike, a lightning-sparked fire that’s been burning since July 15 following a punishing thunderstorm, had grown to 172,797 acres by Wednesday, with 72 percent containment. Crews had continued to make headway on the sizable blaze until Monday when winds blowing up to 30 mph caused the flames to flare back up. That flare up has since tacked on more than 5,000 acres of fire growth due to spot fires spread by the winds. Level 3 — “go now” — evacuations remain in effect for residents of Oak Flat, Old House, Spud Road and along the 33 road in Agness, with a level 2 — “get set” — evacuation advisory for Agness residents north of the Rogue River, according to the Incident Information System wildfire website.
On Tuesday, “fire containment lines were improved and extended along the fire’s perimeter,” the site reads. “Fire crews also worked aggressively to contain the 12 spot fires that were created by last weekend’s wind event. At this time 8 of the 12 have line around them and work is ongoing on the others.”
The Oregon Department of Forestry also continues to work toward full containment on Josephine County’s much smaller Holland Mainline fire, which has been burning southeast of Cave Junction since Sunday. Holding at 81 acres, crews estimated 60 percent containment Wednesday. Firefighters in Klamath County also continue to battle the 500-acre Stukel fire, which was 70 percent contained Wednesday, a news release said.
The sudden bump in fire activity isn’t what prompted the recent fire danger level to be raised back to “moderate” from “low,” which it had originally dropped to Oct. 4, ODF public information office Natalie Weber said. It was the weather forecast.
“For awhile we were getting the cooler conditions with the rain and higher relative humidity, but just in the past four or five days, it’s been a lot warmer, we’ve had the sun out, it’s been 70 degrees and we’ve had really low relative humidity along with the wind,” Weber said. “And that’s kind of the perfect storm for a fire sparking, especially with the dry fuels.”
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