EUGENE -- Oregon's preparations for Saturday's home game against Nebraska have been altered by air quality so "hazardous" that local agencies have issued an alert for residents.

The Ducks will travel an hour to the coast Tuesday morning and practice at Siuslaw Middle School in Florence. The workout is closed to the public and media.

The Lane Regional Air Protection Agency has not recorded levels of particulate matter to this degree since it began measuring for it in 1999, spokeswoman Jo Niehaus said Monday afternoon, and air quality is "absolutely in the hazardous" range, she said.

Four wildfires, or wildfire complexes, larger than 20,000 acres are currently blazing in the state, according to the Oregon Department of Forestry. The state has been hit by high temperatures, as well. It was 90 degrees at kickoff Saturday during Oregon's season opener against Southern Utah, marking just the fifth time in Autzen Stadium history that the temperature was above 90 at kickoff.

LRAPA and the Oregon Department of Environmental Quality on Sunday issued an air quality alert for Lane County and several others that remains in effect until Tuesday evening, warning that wildfires "will cause air quality to reach unhealthy levels due to smoke and ozone at times through Tuesday afternoon." The agencies suggested limiting outdoor activities through the end of the alert. An alert for smoke and ozone was already in effect.

"We're hoping the worst of this clears out Tuesday evening," Niehaus said.

But Tuesday morning is when the Ducks, fresh off a 77-21 season-opening win against Southern Utah, will return to practice. Nebraska (1-0), a two-touchdown underdog as of Monday afternoon according to Vegas oddsmakers, visits Autzen Stadium for a 1:30 p.m. kickoff Saturday.

The National Weather Service in Eugene is forecasting a 20 percent chance of showers and thunderstorms Wednesday, with temperatures in the mid-80s. By kickoff Saturday, the forecast currently calls for 78 degrees and mostly sunny skies.

"We're always going to look what's best for our players," UO coach Willie Taggart said Monday, prior to the decision of moving practice was made official. "We're keeping in touch with our medical staff and they're monitoring how it's going to be. Hopefully we can get out and practice tomorrow. If not maybe we'll go inside (the Moshofsky Center) if it's good to go inside. But we're going to practice."

-- Andrew Greif

agreif@oregonian.com

@andrewgreif