A wildfire raging in Oregon for the past ten days has grown to the fifth largest blaze in the state’s history and is producing “fire clouds”.
The Bootleg Fire has burned through 241,000 acres, an area greater than the size of New York City, and is destroying about 1,000 acres every hour in the southern part of the state close to the California border.
Warnings were issued on Friday over the collapse of “fire clouds” - columns of dust and ash up to six miles (10km) high that spread embers when they fall. The phenomenon caused the evacuation of two communities to the east of the main fire zone on Friday.
There was also the threat of “fire tornadoes”. Also known as a “firenado”, these form when a pyrocumulonimbus cloud is created above areas of intense rising heat sucking in smoke, dirt, and flames.
The Oregon Department of Forestry announced that more than 5,000 homes at risk from fire throughout the state.
Firefighters have been forced to retreat from the Bootleg’s frontline, incident commander Rob Allen toldThe Associated Press, due to its intensity and “explosive” growth.
High temperatures, strong winds, and extreme droughts means conditions remain precarious in Oregon, and across the Western US.
More than 1,900 firefighters and a dozen helicopters as well as airplane tankers and bulldozers were assigned to the Bootleg Fire as demand for personnel and equipment across the country becomes strained.
Some 70 wildfires have burned more than 1 million acres across the US and more than 17,700 wildland firefighters and support personnel are on the ground tackling blazes.
The US wildfire season is feared to be even worse this year than 2020’s unprecedented blazes. The climate crisis is driving the frequency and intensity of wildfires by making conditions hotter, drier and more unpredictable.
The Pacific Northwest and parts of western Canada suffered a historic heatwave earlier this month with triple-digit temperature records broken at nearly 70 National Weather Service stations. More than 100 people died in Oregon alone and hundreds more in neighbouring areas.
Meteorologists are forecasting the arrival of a fourth major heatwave this weekend. A high-pressure ridge is building over the southwest which will drive up temperatures in parts of Northern Rockies and High Plains until Monday.
The Bootleg Fire erupted on 6 July, and its origins are still under investigation.
Additional reporting by the Associated Press