Air quality moderate in Willamette Valley, Portland; red flag warning issued

PORTLAND, Ore. (KOIN) — A buildup of smog is causing moderate air quality levels in the Willamette Valley Tuesday.

The National Weather Service has issued an air quality advisory for the region until 8 p.m. Although smoke from the 6,261-acre Shelly fire burning in Siskiyou County is forecast to pass overhead, KOIN 6 Meteorologist Kelley Bayern reports that the high-elevation smoke isn’t expected to affect Portland’s air quality Tuesday.

“You may notice hazy sunshine today, especially looking towards the south or east,” Bayern said. “Smoke models keep wildfire smoke away from the surface and there should be little to no impact to air quality due to wildfire smoke today in Portland.”

Health officials recommend that sensitive groups, including older adults, children, and people with asthma or lung disease limit outdoor activity Tuesday. 

A red flag warning is also in effect for Central and Eastern Oregon until 11 p.m. due to “critically dry” conditions and the possibility for “extreme” fire growth, the NWS warns.

“A dry and unstable air mass with warm temperatures can contribute to active fire behavior,” Portland’s NWS office stated in response to the red flag warning. “In western Washington, significant growth on existing fires takes place under such conditions. If a fire were to begin, air quality may diminish in the surrounding area.”