Big Rock

Big Rock Fire Report - August 12, 2026

Fire Start, Size and Growth

Start Date/Time/Location: The Big Rock Fire ignited on July 31, 2026 (with official incident reports noting major activity continuing into August 1, 2026), following a lightning strike in the foothills north of Kelly Canyon Road and east of Heise in Jefferson County, Idaho.
Size and Containment: As of August 12, 2026, the fire has burned approximately 2,142 acres and is currently 85% contained.
Fuels, Growth and Rate of Spread: The fire initially spread rapidly through two-foot brush and hazardous vegetation in steep, rugged terrain. While it previously exhibited active behavior that threatened hundreds of homes in its early stages, current fire behavior is minimal, characterized primarily by creeping and smoldering.
Containment Efforts: Ground operations are supported by the U.S. Wildland Fire Service (USWFS) Great Basin Unit 3, the Bureau of Land Management (BLM), the U.S. Forest Service, and the Idaho Department of Lands. Approximately 134 personnel are currently assigned to the incident. Crews have successfully secured containment lines, removed hazard snags, and utilized masticators to clear dense vegetation. Total suppression costs are estimated at $3.4 million. Incident command has now successfully transitioned back to the local unit.

Emergency Information

Evacuations and Sheltering:
Mandatory Evacuation Orders: Initial mandatory evacuations (GO Status) for homes and campgrounds north of Heise to Lyons Creek, and for residents along South Snake River Road, have largely been lifted as containment increased.
Evacuation Warnings: Level 2 "Set" status warnings were previously issued for areas around Table Rock Campground and Wolf Flats. Residents and visitors are encouraged to stay alert to changing conditions.
Curfew: No curfews are currently reported for this incident.
Evacuation Shelters and Information: During the height of the evacuations, an emergency shelter was established at South Fork Elementary School in Rexburg to support impacted individuals.

Road and Infrastructure Closures:
Several closures remain in effect to protect public and firefighter safety as crews continue mop-up operations:

• Heise Road east of the 7N Ranch Resort.
• Kelly Canyon Road.
• River Road, both east of Kelly Canyon and west of the Heise Bridge.
• Camping Closures: Kelly Island Campground, Wolf Flats, Warm Springs, and all dispersed sites along River Road remain closed through Sunday, August 16.
• Trail Closures: Cress Creek Nature Trail, Stinking Springs Trail, and all hiking and biking trails in the Kelly Canyon and Heise areas remain closed.

For more information, visit:

• Idaho Department of Lands Fire Information
• Bureau of Land Management - Idaho
• Bonneville County Sheriff's Office Alerts

Current Impact

Impacts:
Injuries and Fatalities: There have been no reported injuries or fatalities associated with the Big Rock Fire.
Structures Impacted: Despite threatening hundreds of homes in its early stages, no homes, local landmarks, or recreation areas were lost or destroyed thanks to the operational excellence of first responders.
School and Business Closures: Local businesses are recovering; the Heise Hot Springs pools and the 7N Ranch Resort have reopened for regular business hours.
Notable Impacts: The fire significantly impacted local summer recreation, forcing the extended closure of popular campgrounds and trails along the Snake River and South Fork Canyon.

Safety Concerns:
Power Outages: No significant power outages have been reported in relation to this fire.
Water Safety: No specific water safety concerns have been reported, though flash flooding in the burn scar remains a potential risk during thunderstorms.
Burn Bans: The BLM has issued a temporary emergency closure of all BLM-managed lands, roads, and campgrounds along the South Fork Canyon.
Air Quality: Smoke from the fire has been visible from neighboring areas like Teton Valley, but air quality has not reached levels sufficient to severely impact public health.
Other Health Risks: Officials strictly prohibit the use of personal drones near the fire area, as unauthorized drone activity grounds firefighting aircraft and delays critical operations.

Ongoing Outlook

Containment Projections: Firefighters have made steady and consistent progress over the last 72 hours, reaching 85% containment. Crews will remain on the hill throughout the week to patrol the fire perimeter, extinguish remaining hotspots, and prevent any reignitions. Officials anticipate that the fire will remain within its existing footprint.
Weather and Wind Warnings: A Red Flag Warning was recently in effect for the region due to hot, dry, and windy conditions. Forecasts indicate a chance of thunderstorms which may bring heavy rain and gusty, erratic winds up to 20 mph out of the west to southwest. These storms introduce the potential for flash flooding in the recently burned areas.

Cause and the Role of Weather and Climate

Cause: The Big Rock Fire was natural-caused, sparked by a lightning strike on July 31, 2026.
Weather and Climate: The fire was fueled by hot, windy weather conditions typical of the region's fire season, which runs from June to October. Steep terrain and dry brush exacerbated the initial spread. While erratic winds and thunderstorms continue to pose localized challenges for firefighters, the broader national climate context shows that the 2026 wildfire season is currently tracking about 49% below the two-decade average for acres burned.

For more information, visit:

• InciWeb - National Incident Information System
• Idaho Fire Info
• U.S. Forest Service - Caribou-Targhee National Forest