Big Grass Fire Scorches Nearly 300,000 Acres on Oregon-Idaho Border, Communities Under Evacuation

The Big Grass Fire, burning in the rugged high desert along the Oregon-Idaho border, has become one of the largest individual fires in the Pacific Northwest this season, scorching approximately 288,000 to 300,000 acres with only 5% containment as of July 28, 2026. The lightning-sparked fire has prompted Level 3 "Go Now" evacuation orders for multiple communities in eastern Oregon and Owyhee County, Idaho.

Fire Overview

The Big Grass Fire ignited on July 23, 2026, in the high desert approximately 25 miles southwest of Jordan Valley, Oregon. It spread rapidly through dry rangeland grasses and sagebrush under the influence of hot, windy, and critically dry conditions that have dominated the region for weeks. Within days, the fire crossed from Oregon into Idaho's Owyhee County, prompting evacuation orders on both sides of the state line.

As of Tuesday, July 28, the National Interagency Fire Center updated the fire's size to approximately 288,119 acres, though some estimates place the total at or beyond 300,000 acres. Only 5% of the fire's perimeter has been contained, with 135 personnel, 14 engines, and seven dozers working the line.

Affected Communities and Evacuations

The fire is threatening agricultural land, ranches, and small communities in one of the most sparsely populated areas of the West. Current evacuation orders include:

Level 3 (Go Now): Pleasant Valley, South Mountain, and Jordan Valley communities and surrounding rangelands in eastern Oregon
Level 1 (Be Ready): Portions of Owyhee County, Idaho, where the fire has burned across the state line

The fire is also affecting working ranches across the region, with impacts to livestock operations, fencing, and grazing land. Malheur County and Owyhee County emergency management offices are coordinating response efforts on both sides of the border.

Terrain and Suppression Challenges

The fire is burning in the vast, remote terrain characteristic of the high desert — rolling hills, dry creek drainages, sagebrush-steppe, and grass-covered ridgelines that burn fast and hot. Road access is limited in many portions of the fire area, hindering suppression efforts and the delivery of resources to the fire's edge. Helicopters are playing a critical role in reconnaissance and water drops where ground crews cannot operate.

Cause and Fire History

The cause of the Big Grass Fire has not been officially determined, though it ignited during the same period of severe lightning activity that sparked dozens of other fires across the Pacific Northwest. The Oregon-Idaho border region has seen multiple large fire events over the past decade as climate conditions have pushed fire seasons earlier and more intense into the high desert.

Stay Informed