The Cow Valley fire in eastern Oregon’s Malheur County continued its advance south Friday night, growing to an estimated 81,000 acres while sending up flames visible from homes in Vale.

As of Saturday morning, the fire was eight to 10 miles north of the city, burning in rangeland. The fire had reached the Turner Creek area, about five miles south of the fire’s edge on Friday morning at Gum Creek.

Fire crews trying to check the spread of the fire, which has quadrupled in size from the 20,000 acres that were burning early Friday morning, face another challenging day as temperatures are again forecast to hit 100 or higher and lightning from dry thunderstorms is anticipated by Saturday afternoon.

A new incident command center is being established at Vale Elementary School. A federal team trained in handling major fires is scheduled on Sunday, July 14, to take over management of the fire, bringing in specialists in everything from air support to fire behavior. The Northwest Management Team will be joined by Red Incident Management Team from the state fire marshal’s office.

According to the federal incident web page for the fire, the fire teams will be “working on identifying contingency lines. Continue to scout ahead of fire to look for opportunities for burn operations and to build containment lines. Continue to make improvements on the heel of the fire.”

The fast-spreading fire started Thursday morning along Indian Gulch Road in Cow Valley in an area of open range northeast of Ironside. Officials say the fire was human caused but have released no other details on what started the conflagration.

Erratic winds and high temperatures have resulted in severe fire behavior, authorities said. The attack on the fire has largely been done from the air because of the rugged terrain and the extensive fire front. Up to 16 aircraft at a time have been pressed into duty, with tankers ranging from single-engine aircraft based in Ontario to the lumbering larger jets, have been painting the range for days with retardant.

Fire crews worked through the night Thursday night to spare the rural community of Brogan. Dozers cut a safety line entirely around the community as the fire bypassed Brogan and burned south to the Cottonwood Mountain area, which is west of Jamieson.

In a Friday night update, the Bureau of Land Management reported 120 people assigned to the fire with nine engines, two water tenders, five dozers and one hand crew.

They got help from teams of firefighters brought in from across Oregon, tasked with protecting 45 homes and buildings in the Brogan area from the fires. The task forces were dispatched to the Cow Valley fire by Oregon State Fire Marshal Mariana Ruiz-Temple. Gov. Tina Kotek declared the fire a conflagration, clearing the way for the state to send more help.

Officials on Friday afternoon opened U.S. Highway 26, which had been shut down from Brogan to Ironside because of fire burning on both sides of the highway. Motorists were urged to use caution traveling through the area because of the fire equipment traffic.

In Vale, the elementary school at 403 “E” Street W. was being transformed into a fire camp.

Alisha McBride, Vale School District superintendent, alerted the community to the development in a statement Friday night.

“For the safety and efficiency of our emergency responders and their operations, we kindly request that community members refrain from visiting the Vale Elementary School and Vale Middle School campuses, parking lots, and grounds,” she said.

CORRECTION: An earlier version of this story misidentified Gov. Tina Kotek.