Fire crews were battling about 50 new wildfires in eastern Lane County on Monday, blazes ignited by hundreds of lightning strikes from Sunday evening's thunderstorm.
Today could bring more thunderstorms to the valley and the central Cascades and a sharp cooling trend.
Most of the fires are along the Highway 58 and Highway 126 corridors, including the largest, a 25-acre fire about three miles southwest of Dexter Lake. That fire, which isn't threatening any residences, was 60 percent contained Monday evening and crews planned to continue fighting it overnight, state Department of Forestry officials said.
Other significant fires included two 5-acre blazes near Oakridge and an up-to-10-acre fire on the slopes of Mount Hagan near Blue River, all of them in the Willamette National Forest. Many of the other fires in the forest were much smaller -- a tenth of an acre or less -- said Jude McHugh, a spokeswoman for the U.S. Forest Service, but none of them had been fully extinguished by early Monday evening.
None of the fires is posing any immediate threat to residences or other buildings in eastern Lane County.
About 120 firefighters, 20 fire engines and seven helicopters were involved in Monday's operations.
With more thunderstorms expected Monday evening and today, officials were bracing to deal with a new rash of burns.
"We're hitting these fires hard, trying to get them out, so we can be ready for the next ones," said Link Smith, a forester with the state forestry department. "With all the fires here and elsewhere, (firefighting) resources are hard to come by right now."
Firefighters are battling at least 26 large fires across Oregon, Washington and Idaho, and they're bracing for dozens more with the anticipated lightning strikes.
The Northwest Interagency Coordination Center in Portland, which monitors forest fires regionwide, expects dry lightning, followed Wednesday or Thursday by some rain.
"We're in for it, I think," center spokeswoman Carol Connolly told The Associated Press.
None of the big fires is in Lane County, but their smoke has periodically sullied local air quality.
McHugh said that the Forest Service will use a patrol plane and its lookout towers to spot new fires early this morning in east Lane County. Fires on federal forest lands can also be reported by calling either 911 or 541-225-6400, she said.
"The fires keep coming, and we keep finding them and dealing with them," she said.
McHugh added that, despite the dry conditions on Monday, low winds kept the fires from growing at an alarming rate.
Further north, two quarter-acre grass fires were ignited Sunday night by lightning off Highway 34 in Lebanon, the Lebanon Fire District said.
At 9:18 p.m., firefighters were dispatched to a grass fire on 32843 Sand Ridge Road when they noticed a newly ignited fire at 36159 Airport Road, fire officials said.
Twenty fire personnel were called to respond to both fires.
Meanwhile, crews continue to battle the 2-week-old and growing Staley Complex -- three fires totaling 194 acres located on steep and rocky terrain 25 miles southeast of Oakridge. A total of 405 firefighters are at the complex where helicopters are being used to drop water on the fires, which ground teams cannot easily access.
On Monday, officials closed several Forest Service roads in the area to the public, citing safety concerns. However, increased humidity due to rain has slowed the fires' growth, officials said.
Thunderstorms are expected to continue, but be more scattered, over both the Willamette Valley and the Cascade Range today and Wednesday, said Laurel McCoy, a Portland-based National Weather Service meterologist. Those storms will likely bring more rain, she said, which should cut down on the fire risks.
The storms will keep moving east, likely only hitting the Cascades by Thursday, she said.
The intense heat, humidity and thunderstorms are being caused by hot, moist air masses rolling into Lane County from the east and southeast, and encountering cooler air pushing inward from the Pacific Ocean.
Smoke from the forest fires in east Lane County caused air quality in both Oakridge and Eugene/Springfield to drop from good to moderate throughout Monday, according to the Lane Regional Air Protection Agency.
Intermittent winds coming from the east are pushing the smoke into the Willamette Valley, said agency spokeswoman Jo Niehaus.
Niehaus said she's expecting the valley's air quality to fluctuate between moderate and good for the rest of this week.
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