Several blazes, including a 'megafire,' growing in Oregon amid dry fuel and high temperatures

A slight respite from hot, dry weather Monday slowed the hunger for acreage among Oregon’s eight major wildfires, but an ominous forecast loomed as the state welcomed outside help.

Oregon’s largest blaze, the Cow Valley Fire along the state’s desolate eastern flank, stood at 132,528 acres Monday, with 5% containment reported late Monday along its 163-mile perimeter, according to the U.S. Forest Service, other federal agencies and state fire officials.

When it surpassed 100,000 acres sometime late Friday or early Saturday, the blaze became what the U.S. Interagency Fire Center deems a “megafire.”

Early Monday, the winds that sustained roaring flames and their consumption of dry, 3-foot-tall brush died down, slowing the fire’s expansion and giving firefighters hope of victory, the agencies said in a daily update.

Citing critical fire danger, Gov. Tina Kotek on Monday declared an extended state of emergency in Oregon. On Friday, she had invoked the state’s Emergency Conflagration Act to bring more resources to the Cow Valley Fire, which started the previous day.

“Wildfires are active across Oregon and are growing at a concerning pace,” Kotek said in a statement Monday. “Hot and windy conditions this weekend, including forecasted lightning in some areas, are threatening even larger wildfires.”

Just south of the megafire is the 2,275-acre Bonita Fire, reported Monday to be 40% contained, federal agencies said. Both blazes were under the management of the Cow Valley Fire federal task force.

Both were characterized as human-caused, although an exact mechanism and who was behind those origins appeared to be unknown, with state and federal authorities investigating.

Kotek’s actions were bolstered by two Oregon State Fire Marshal task forces assigned to the Cow Valley Fire and help from two Washington state task forces, the fire marshal’s office said in a statement Monday.

The weather was enough of a help Monday — a high pressure dome that had been baking the West since early this month shifted to the east and deflated temperatures by 4 to 10 degrees in parts of Oregon — that the task forces were being moved to other fires, the office said.

In addition, evacuation readiness levels near the Cow Valley Fire were downgraded Monday in some cases, although the Westfall area was under “get ready” status, which urges residents to be packed, charged and fueled up as flames near, according to the Malheur County Sheriff’s Office.

Resources from Alaska, Colorado, Florida, Georgia, Hawaii, Idaho, Montana, New Mexico, Oklahoma and Texas, as well as from the Canadian provinces of Alberta, British Columbia, Saskatchewan and the Yukon and Northwest Territories, were also being assigned to the state’s major fires, the fire marshal’s office said.

The state’s second-largest fire is the Falls Fire in Malheur National Forest, about 5 miles southwest of Butte Falls, according to National Interagency Fire Center information.

The blaze was measured Monday at 64,225 acres, with no containment, federal agencies said in a daily update. Unwelcome winds as strong as 20 mph were expected Monday night, the update said.

Parts of Grand and Harney counties were under mandatory evacuation orders, and authorities closed down U.S. Highway 395 near the community of Riley on Monday evening as the fire raged nearby.

Oregon’s eight fires had consumed about 250,000 acres by Monday, the National Interagency Fire Center said. Four people have been injured and four structures have been destroyed in the Cow Valley Fire and the Falls Fire, the state said on its fire information dashboard.

The National Weather Service office in Portland said hotter temperatures would return this week and continue to climb into the weekend, with a 10% to 20% chance of lightning starting Tuesday. Inland areas of the state could get high temperatures of 95 degrees by the weekend, the weather service said.

A red flag warning calling for dry conditions and possible lightning strikes was in effect Monday night for an area east of the coastline in the extreme northern reaches of California to Medford, Oregon.

The National Interagency Fire Center urged summer travelers to be cautious and careful.

“We cannot stop the hot weather and lightning storms, but we can do our part to be fire wise when we are recreating, traveling, or staying home,” it said in a daily report Monday. “Take the time to find out the weather conditions and fire danger where you live and plan to vacation.”