A wildfire season affected by drought and a warm winter is revving up early, as multiple fires blaze across Western states.

Three firefighters died on Saturday in a fire raging along the Utah-Colorado border. State and local authorities have declared emergencies. People in neighborhoods in several states have been told to evacuate or to prepare to leave their homes at any moment. Light filtering through the smoke is casting an orange glow over large parts of the region.

Here’s what we know about the fires:

Where are the wildfires?

Fires are burning in Colorado, Utah, Arizona, New Mexico and Nevada as gusts of wind pummel a landscape full of dry fuel.

Cottonwood fire: The largest blaze in Utah, the fire began near Beaver, a city in the southwestern part of the state. It has burned for about a week, destroying a ski lodge, campgrounds, homes and infrastructure and forcing evacuation orders. Gov. Spencer Cox of Utah said it appears to be the “most destructive fire in the state’s history” as measured by property loss. No injuries or deaths have been reported. As of Monday morning, the fire had consumed more than 93,000 acres, and none of it had been contained.

Snyder fire: The fire, which formed over the weekend and has grown as fires merged along the Colorado-Utah border, has devoured more than 28,000 acres, with none of it contained. Gov. Jared Polis of Colorado declared a disaster late Saturday, activating the state’s National Guard.

Gold Mountain fire: The fire, which began Saturday in Ouray County, Colo., now covers more than 4,000 acres. Mr. Polis declared a disaster in response to the blaze on Sunday after it grew to about 570 acres. Some residents north of the city of Ouray, including in the Panoramic Heights and Lake Lenore areas, were ordered to evacuate.

Pocket fire: The Pocket fire in Arizona nearly doubled in size overnight. It measured more than 6,000 acres Sunday and about 11,000 on Monday. The blaze, which began June 19, is tearing across steep terrain north of Sedona. Some residents of areas east of the fire have received a warning telling them to be ready to evacuate at any time.

For updated information on nearby fires and fire conditions, residents can use the Watch Duty app or the National Interagency Wildfire Enterprise Geospatial Portal.

Who are the firefighters who died?

Three firefighters died on Saturday: Emily Barker, 38, of Clinton Township, Mich.; Nick Hutcherson, 27, of Glendale, Ariz.; and Sydney Watson, 27, of Warrior, Ala.

They were responding to the Knowles fire in western Colorado. They were suddenly overwhelmed by flames and tried to take shelter, the U.S. Department of the Interior said in a statement on Sunday. Two additional crew members suffered burn injuries. The blaze is now part of the Snyder fire.

The department said on Monday that investigators were examining what happened.

“This is an incredibly difficult moment for the entire wildland fire community,” Sarah Fisher, deputy chief of the Forest Service, said in a statement. “Our heavy hearts are with the families during this unimaginable time.”

What areas are affected by smoke?

Wildfire smoke can blanket cities and states far from the areas that are ablaze. Wind may disperse tiny particles of soot, ash and dust for hundreds of miles.

Officials have warned people in areas with unhealthy air quality to stay indoors, if possible, with their doors and windows closed.

People can check air quality using the Environmental Protection Agency’s AirNow website or on the PurpleAir map, which compiles data from a network of crowdsourced sensors.

Will conditions improve?

Not for a while. Colorado and Utah, like other states across the West, recorded historically low amounts of snow last winter, resulting in drier conditions this spring and summer that have left the landscape parched and highly flammable.

“The conditions we’re seeing right now, we usually don’t see until mid-July to August,” Karl Hunt, a spokesman for the Utah agency that oversees forestry and wildfires, said last week.

The National Weather Service said that hot, dry and windy conditions across the region would continue to pose a challenge for firefighters this week. The most dangerous conditions are expected on Tuesday, when parts of eastern Utah and western Colorado could experience wind gusts up to 35 miles per hour, with extremely low humidity.

Bernard Mokam, Jack Healy, Benjamin Wood and Nancy Lofholm contributed reporting.