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If a record-breaking heat wave doesn't lift soon, cattle rancher Sharon McDonald may see her hay crop turn to dust.

Oppressive temperatures eased a bit Friday in some parts of the West, but McDonald's central Montana ranch baked under triple-digit heat. Forecasters reported little relief in the days ahead, saying the weather system that brought the high temperatures could last well into next week.

In Montana, where cattle outnumber residents by more than 2 to 1, livestock and people sought shade and drought-weary farmers watched for damage to grain.

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"We are trying to get our hay up before it disintegrates," said McDonald, a rancher near Melville. "It just gets crispy and just falls apart."

Extreme heat plagued much of Idaho, Nevada, Utah, Oregon and Washington state.

Air conditioners — and even swamp coolers — were predictably hot sellers at the hardware store.

"I'm telling you, it has been nuts," said Dennis VanDyke, a manager at Power Townsend in Helena. "The only thing I am getting calls for is air conditioners."

VanDyke said some people prefer swamp coolers, which use a fan and the condensation of water to cool the air, over the more power-hungry air conditioning units.

"They are being bought faster than we can put them on the shelves," he said.

In Montana, temperatures above 100 degrees are usually not seen until August. The normal July high in Helena is 83 degrees — not the high 90s seen Friday. Triple-digit records were set or tied in several Montana cities, including Great Falls and Billings at 104 degrees each. The mercury reached 105 in the north-central Montana town of Havre and at the Gallatin Field Airport near Bozeman.

In Utah, high school teacher Lois Wolking said she was escaping the summer heat by heading indoors. Temperatures were down a few degrees in Salt Lake City on Friday, but still hovered around 100.

"A swamp cooler, Netflix and reading is how we're surviving," the 58-year-old East High teacher said.

Boise, Idaho reached 105 degrees Friday, and some found it too hot to play at a public water fountain.

"We'll probably leave soon. Two or three o'clock is about my limit before I want to get in some air conditioning," mother Monica Player said as children ran through jets of water.

Temperatures were expected to ease slightly in Southern California. Phoenix saw a modest drop, a somewhat cooler 112 degrees compared to 115 on Thursday. With the approach of Arizona's summer rainy season, humidity levels have started climbing along with power demand.

Heat remained an issue along the border. The bodies of six suspected illegal immigrants have been found since Monday in southern Arizona deserts, all likely victims of heat illness while trying to walk into the U.S. from Mexico. The toll, while high, is not unusual during hot spells in the region.

In eastern Oregon, which set 15 record highs on Thursday, temperatures largely dropped to the high 90s. In the center part of the state, population growth and a burgeoning demand for air conditioning meant a rise in electricity demand. The Bonneville Power Administration said it was worried fires could damage transmission lines and cause outages.

Officials said the fire season could turn fearsome following the dry heat.

"It's an early start and a hot start," said National Weather Service meteorologist Chris Velver in Great Falls.

The National Forest Service reported at least 16 fires over 500 acres in size burning throughout the West, including three new ones that sparked Thursday.

The agency said fire danger was most extreme in Arizona, California, Oregon and Utah — although a "red flag" warning was posted for much of the West.

In Wyoming's Grand Teton National Park, rangers used a helicopter Thursday evening to rescue a backcountry hiker after he suffered symptoms of heat exhaustion and acute mountain sickness.

In California, heat was mostly confined to inland regions, with triple-digit readings in the Sacramento and San Joaquin valleys.

The mercury topped 100 in the Woodland Hills area of Los Angeles' San Fernando Valley and in the high desert cities of Lancaster and Palmdale, while out east by the Colorado River, the little city of Needles sweltered in 115-degree heat.

But temperatures in most of Los Angeles and the populous Southern California coastal zone were in the 70s and low 80s, while San Francisco and Monterey Bay cities were even cooler.

In Montana, temperatures could start to fall by Saturday, forecasters said.

But the heat will hover over most of the far West through at least the end of next week, said Kelly Redmond, a regional climatologist for the National Weather Service. He said it could migrate further inland and cover more of the West, including Colorado, as the week goes on.

"It looks like it is going to stay place for a good long while," he said.

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