Wildfire smoke is blanketing much of the West and heat waves persist. Photo: Nick Sulzer // Buckrail

BILLINGS, Mont. (AP) — Extreme heat descended on parts of the U.S. northern Rocky Mountains on Monday, as authorities struggled to contain dozens of wildfires burning in a region parched by prolonged drought and blanketed with dangerous smoke.

Record-setting temperatures were forecast for much of eastern Montana and portions of northern Wyoming.

Billings, Montana’s largest city, was expected to hit 106 degrees Fahrenheit (41 Celsius), topping a record set 61 years ago. Glasgow was forecast to reach 108 F (42 C).

The heat will linger through Thursday, the National Weather Service said.

Extreme conditions like these are often from a combination of unusual random, short-term and natural weather patterns heightened by long-term, human-caused climate change. Scientists have long warned that the weather will get wilder as the world warms.

Climate change has made the West much warmer and drier in the past 30 years. Special calculations are needed to determine how much global warming is to blame, if at all, for a single extreme weather event.

Red flag warnings for high fire risk were issued across almost all of Montana and Idaho and portions of northeastern and western Wyoming. More than two dozen new fires broke out across the three states Sunday, further straining firefighting resources already stretched thin by a high number of early summer fires.

Thunderstorms rolling through on Monday night will bring winds that could fan wildfires and lightning that could spark new ones, according to the weather service.

Meanwhile, smoke continued to pour into the skies over the region from local blazes and fires elsewhere in the West, causing unhealthy air quality around numerous Montana cities Monday morning — including Missoula, Anaconda, Butte, Great Falls, Cut Bank and Browning — and around McCall, Idaho, according to state and federal pollution monitoring data.

When the air quality is unhealthy, people should remain indoors as much as possible and limit themselves to 30 minutes of light outdoor activity.

Air quality in Butte, Havre, Helena and Missoula was unhealthy for sensitive groups, which includes children, pregnant women, older adults and people with chronic disease, such as asthma or cardiovascular disease.

A Montana firefighter was hospitalized in serious condition at the University of Utah Burn Center in Salt Lake City for burns he suffered when strong winds shifted suddenly on a fire in south-central Montana.

Dan Steffensen was injured fighting a fire in the Harris Hill area near Joliet, which has torched 4 square miles (10.5 square kilometers) of land. Steffensen was on a two-person engine crew when the winds shifted and he was overrun by the fast-moving fire, Red Lodge Fire Rescue said.

A Montana Highway Patrol trooper who helped rescue the crew of a downed firefighting helicopter last month was to be given Monday the Award of Valor, the patrol’s highest award.

Trooper Amanda Villa was setting up a roadblock for a fire on June 15 when she saw a Department of Natural Resources and Conservation helicopter make a hard landing near U.S. Highway 12 east of Townsend due to strong winds. Villa and a Broadwater County sheriff’s deputy responded to help.

A passenger who was able to get out of the helicopter told Villa that four more people were inside. She and the deputy helped the remaining passengers to safety as the helicopter and nearby grass burned.