As hot, dry weather conditions continue to fuel wildfires across a lot of the United States, the Bootleg Fire in Oregon has become so intense that it’s creating its own weather system.
The Bootleg Fire has scorched over 530 square miles — that’s larger than Los Angeles and about half the size of Rhode Island. It grew to nearly 364,113 acres Monday (July 19) and is 30% contained, Oregon Department of Forestry spokesperson Marcus Kauffman told CNN.
It’s one of at least eight large fires burning in Oregon and one of at least 80 burning across 13 states, according to the National Interagency Fire Center.
Nearly 3.5 million people have been issued red flag warnings, according to a tweet from the National Weather Service Weather Prediction Center. A red flag warning means “critical fire weather conditions are either occurring now, or will shortly,” the prediction center said.
🌡 Much of the Northwest is under heat and fire related warnings today as a persistent upper-level ridge draws warm and dry air into the region. Parts of the Northern Plains, which are under an Excessive Heat Warning, may break high temperature records today. pic.twitter.com/8H6nzcyjSf— NWS Weather Prediction Center (@NWSWPC) July 19, 2021
Excessive heat warnings will continue for more than 337,000 people, and nearly 650,000 more are under a heat advisory.
A satellite image posted by the weather service shows smoke from the fires in western Canada and the Intermountain West swelling over the region.
As the sun sets across the central and eastern United States this evening, smoky skies fill the horizon due to distant wildfires burning across western Canada and the Intermountain West.🌇 pic.twitter.com/SCGbP9khVK— NWS Weather Prediction Center (@NWSWPC) July 19, 2021
In Oregon, fire officials noted the Bootleg Fire is showing “aggressive surface spread with pyrocumulus development.”
Pyrocumulus clouds form when extreme heat from the flames of a wildfire force the air to rapidly rise, condensing and cooling any moisture on smoke particles produced by the fire. These clouds essentially become their own thunderstorms and can contain lightning and strong winds.
The fire is “so large and generating so much energy and extreme heat that it’s changing the weather,” Spokesperson Kauffman explained. “Normally, the weather predicts what the fire will do. In this case, the fire is predicting what the weather will do.”
Kauffman anticipated the massive blaze will continue to grow adding, “The fire is burning dense fuels that are extremely dry from a prolonged drought. Up until today, the weather has been consistently hot, dry with near single digit humidity.”
The Bootleg Fire began on July 6 in the Fremont-Winema National Forest near the California border; more than 2,000 people are currently evacuated from their homes, Fire Public Information Officer Sarah Gracey said.
The fire has averaged a rate of spread nearly 1,100 acres per hour for more than 13 consecutive days — a rate that would burn through New York’s Central Park in just 45 minutes.
With wind gusts expected to hit up to 25 mph over the next couple of days, there is little hope for dwindling the flames any time soon.
The Bootleg Fire is the third-largest wildfire in the state’s history, Kauffman said. The Long Draw Fire in 2012 burned 557,028 acres and is the largest wildfire in Oregon since 1900. The Biscuit Fire in 2002 became the state’s second-largest fire, burning nearly 500,000 acres.