The Big Rock Fire outside of Heise roughly doubled in size Saturday, exploding to an estimated 2,400 acres as extreme fire behavior — driven by high winds, scorching temperatures and bone-dry terrain — pushed the blaze in multiple directions all at once.
At one point, the wildfire pressed right up against containment lines near homes, close enough that crews had to divert resources to directly defend the threatened structures.
Once again, firefighters held the line. No residences were lost.
It was as close a call as this fire has produced yet, and authorities aren't taking any chances.
A new Level 3 "Go" evacuation order — effective now — covers all homes and campgrounds north of Heise, extending north to Lyons Creek Road and 9000 South, and east to 7000 East, just west of Luthy Meadows, according to Jefferson County and Madison County officials.
The wildfire that ignited Friday is threatening the area and authorities are telling residents in blunt terms: do not delay, do not attempt to remain, leave now.
As fire crews raced to protect homes Saturday, the flames kept moving — spreading southwest toward Cress Creek, northeast onto Idaho Endowment lands south of Moody Creek, and spotting embers east across Little Kelly Canyon and into Kelly Canyon itself. Crews are now working to build containment lines on the west end near Cress Creek, while also developing a strategy to use Kelly Canyon Road to protect Kelly Canyon Resort and the land beyond it to the south and southeast.
By late Saturday afternoon, the fire had shifted direction yet again — pushing northeast, according to Madison County Emergency Management. Federal lands in the area have been closed to recreational use while the fire continues to move. Anyone still in a campsite in the area is being told to leave immediately and head toward Rexburg.
"Please comply with the requests from our first responders," Madison County Emergency Management said. "Thanks and be safe out there."
Through the fire's first long and brutal night, firefighters battling the Big Rock Fire had already won one battle that mattered — even as the wildfire exploded in size and tore through the hills outside Heise, every home, business and campground in its path remained standing. The only structures lost overnight were two unused sheds, according to the Jefferson County Sheriff's Office, a loss confirmed by firefighters actively protecting the buildings on scene. That toll held as Saturday night arrived and firefighters are determined it stays that way.
But weather conditions Sunday are not expected to offer any relief. The National Weather Service has issued another Red Flag Warning for gusty winds, high temperatures and low humidity — the same combination that fueled Saturday's extreme fire behavior — and officials are bracing for another day of significant, potentially extreme fire growth.
"Fire behavior" is no longer just active — fire officials now describe it as extreme, running, crowning and spotting long distances, meaning the fire is moving fast through the ground cover, climbing into treetops, and throwing embers well ahead of the main fire to ignite new spot fires far from the front line. Authorities still aren't guessing on when the blaze will be contained or controlled.
The danger has now spread across three counties. Evacuation status now spans all three levels of the Ready, Set, Go system: the Level 3 "Go" order remains in effect for homes and campgrounds north of Heise and for residences north of the Snake River from Heise Hot Springs east to the "Y" at Kelly Canyon and Forest Service Road 218, extending north to East 12000. Table Rock and Wolf Flats campground areas remain under a Level 2 "Set" evacuation warning. And residents along South Snake River Road, north of the Snake River and up to 10000 North, are now under a Level 1 "Ready" status, the earliest stage of evacuation preparedness.
Residents can check whether they're in a Ready, Set or Go zone at warn.pbs.org.
Getting out safely has become its own challenge. Fire equipment and personnel are currently working the area from the Heise River Bridge east to Kelly Canyon, and officials asked anyone preparing to evacuate to stage along Snake River Road until crews can clear equipment from the roads. Deputies are patrolling the area to guide people out and update them when roads reopen.
There have been no reports about anyone being injured as a result of the fire.
The U.S. Wildland Fire Service's Great Basin Unit 3 – Idaho Falls, several local fire departments and the U.S. Forest Service continue to throw everything they have at the blaze: engines, dozers, hand crews, water tenders and air support, all converging on the fire as fast as they can move. But officials acknowledged Saturday that resources are being stretched thin by the extreme fire behavior, even with an aggressive full-suppression strategy in place.
Every road into Heise and Kelly Canyon remains sealed off, and officials say they'll stay that way until fire crews say it's safe.
"Avoid the area and follow all evacuation orders," Idaho State Police warned via Facebook as troopers moved in to help lock down the roads Friday evening.
The fire's reach now extends well beyond dry land. The Bureau of Land Management issued a formal closure order Saturday shutting down BLM-managed lands, roads, campgrounds and trails throughout the South Fork of the Snake River Canyon from Conant Boat Access to Byington Boat Access. All river camping — including at Kelly Island, Wolf Flats, Warm Springs and every dispersed site along River Road — is prohibited from 6 p.m. Saturday through 11:59 p.m. Aug. 10. The South Fork is also closed to boaters from Byington Boat Access downstream, though boaters currently in the canyon will be allowed to take out at Byington. The Cress Creek and Stinking Springs trails, along with every other hiking and biking trail in the Kelly Canyon and Heise areas, are closed as well.
This isn't a suggestion. Anyone who violates the closure could be tried before a U.S. magistrate, fined and imprisoned for up to 12 months, according to the formal order signed by acting Upper Snake Field Manager Bret Herres. BLM law enforcement will be actively monitoring the area for compliance.
The Idaho Department of Lands has also temporarily closed state endowment lands in the Kelly Canyon block south of Moody Creek, about 5 miles east of Ririe, as the fire pushed directly into that area Saturday afternoon.
The emergency response has been expanding exponentially ever since the fire was first reported around 5:30 p.m. Friday. Firefighters from Jefferson, Bonneville and Madison counties are all on scene, alongside firefighters from federal agencies, waging war against the flames.
As evacuees poured out of the canyon, the American Red Cross of Idaho and East Oregon scrambled just as fast, first establishing a shelter in nearby Ririe at The Church of Jesus Christ of Latter-day Saints, 14061 N. 130 Road E. As the fire's danger zone grew Saturday, the shelter relocated to South Fork Elementary School, 7163 S. 2000 W. in Rexburg.
Volunteers are on-site with food, water and whatever comfort they can offer to people who left their homes not knowing what they'll find when they return. Everyone is welcome.
Anyone who needs help can call 800-RED CROSS (800-733-2767).
And fire officials have one more urgent plea, aimed squarely at the sky: stay out of it. A single stray drone can force helicopters and air tankers to ground immediately — grounding the very aircraft racing to save homes.
"If you fly, we can't," officials said.
For anyone still watching the approaching smoke and wondering if it's time to go: don't wait. The Red Cross says grab essential medications, clothing, identification, phone chargers, an emergency kit, comfort items for kids, and supplies for pets — but only if there's time. If there isn't, leave anyway.