Aug 9, 2021 - Science

107 large wildfires rage across West as "dangerous" heat wave looms

Firefighters try to extinguish Dixie Fire near Chico in Greenville, California, United States on August 5
Firefighters try to extinguish flames from the Dixie Fire near Chico in Greenville, Calif., on Thursday. Photo: Neal Waters/Anadolu Agency via Getty Images

Forecasters are warning Americans to brace for another extreme heat wave this week, as 107 large wildfires burn across nearly 2.3 million acres of the U.S. West.

Driving the news: "Widespread air quality alerts and scattered Red Flag Warnings stretch from the Northwest and Northern Rockies to the High Plains, as well as throughout parts of central California," the National Weather Service said Sunday.

"It's going to be a real oppressive week with dangerous heat and hot conditions across much of the U.S. Excessive heat watches are up across much of the Pacific Northwest for mid to late week, including in the Portland and Seattle metro areas. Meanwhile, heat advisories are in effect for a good part of the south-central U.S. and parts of western New York state."
— NWS

State of play: The massive wildfires were burning across 15 states on Sunday —with weather conditions already dangerous in several places, according to the National Interagency Fire Center.

  • The Dixie Fire, California's second-biggest wildfire in the state's history, is the largest blaze now burning in the U.S. It has destroyed 627 buildings, damaged 42 other structures and razed 489,287 acres as of Sunday night.
  • "Near critical conditions with wind gusts up to 45 mph were reported over north central Montana, and up to 30 mph in eastern Oregon," the NIFC noted in its statement.
  • "These winds caused active fire behavior on the Whitmore, Green Ridge, Black Butte, Thorne Creek, and Woods Creek fires. Extensive smoke continues to blanket California, although many wildfires were active in the late afternoon."

By the numbers: Per the NIFC on Sunday, 25 large fires were burning in Montana, 20 in Idaho, 16 in Oregon, 13 in Washington state, 11 in California, 10 in Alaska and four in Wyoming.

  • Colorado, Utah, Nevada, Arizona, Minnesota, South Dakota, Nebraska and New Mexico had each reported one large fire burning.

What to watch: "The fire outlook continues to reflect warmer and drier conditions leading to the high potential for severe wildfire activity throughout the western United States through the rest of summer and into the fall," per the NIFC.

  • "Widespread high temperatures observed across areas in the West and with periods of lightning activity continue to exacerbate the wildfire situation."

The big picture: The past few months have already seen an unprecedented, deadly heat wave in the Pacific Northwest, with wildfires raging well ahead of peak fire season.

Editor's note: This article has been updated with details of the UN climate report.

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