- The National Weather Service announced that more than 40 million people in the Western U.S. are under a heat advisory or excessive heat warning.
- Power grid operators in California and Texas are vigilant as areas hit triple-digit temperatures.
- Scientists say people living in the American West can expect more devastating heat waves in the coming years.
A long-lasting heat wave brought more triple-digit temperatures on Wednesday, raising concerns that such extreme weather could become the new normal in the Western U.S.
The National Weather Service, the U.S. government agency that provides weather forecasts and severe weather warnings, announced Wednesday that more than 40 million people in the Western region are under a heat advisory or excessive heat warning. At least 11 states reported triple-digit temperatures, Accuweather confirmed.
But the persistent heat wave felt across the West isn't going away anytime soon.
"No easy way to say this, so we'll just cut straight to the chase: it's going to be *very* hot for a *long time* next week," the National Weather Service in Salt Lake City said on Twitter Friday. "The entire area is going to be way above normal for all of next week."
The weather service said that residents "enduring the abnormal heat" are urged to stay hydrated and avoid extended periods of time outdoors if possible.
"With warm temperatures and dry soil in place, an elevated fire risk is in effect throughout portions of the Rockies and Intermountain West," the service wrote.
At least four states have issued evacuation orders for residents. Here's a look at the hottest it will be in the Western states and when it may end:
Arizona 'flirting with records'
Phoenix temperatures hit 115 degrees Tuesday, falling just short of a daily record set in 1974 but marking the highest temperature in the city so far this year. Wildfire smoke from nearby Telegraph Fire was lowering the temperature in the city.
But Phoenix is expected to hit 115 degrees Wednesday and 117 the next two days, the National Weather Service said. The record for Wednesday had been set at 115 degrees in 1974.
Phoenix's low temperature on Wednesday morning was 90 degrees, which the National Weather Service said could set a new record-warm low if it holds through midnight. The current record was 86 degrees, set in 1988, according to the National Weather Service.
The excessive heat warning for the state is expected to end Sunday night.
"It's just going to be very hot and we'll be flirting with records each day," meteorologist Matthew Hirsch said of the week ahead. "We don't see cooling trends really until late in the weekend, early next week.
"It's not normal, it's unusual to be this hot," Hirsch continued, adding that normal high temperatures were usually around 105 to 106 degrees this time of year. "It's just a very warm and dry air mass that's moved northward into the region and very high pressure with it."
Meanwhile, Southern Nevada will be experiencing near-record or record heat until Saturday, the National Weather Service in Las Vegas said. Las Vegas Wednesday topped an 80-year-old record for June 16, recording a high of 116. The previous high was 114, set in 1940, and the all time high for Las Vegas is 117, according to the Las Vegas Review Journal.
Sizzling temperatures in California, Texas put grid operators on alert
Tuesday, Palm Springs, California, hit 117 degrees, appearing to break the record high temperature for June 15 set in 1961. It hit 120 on Wednesday, reports said.
The forecast high temperature in Death Valley, California, on Wednesday was 124, just 10 degrees shy of the highest temperature recorded in the area and in the world, 134 degrees Fahrenheit in 1913.
Record high temperatures are also expected in Northern California and in the Central Valley. High temperatures 10 to 20 degrees above average will spread into central and northern California through Thursday, the National Weather Service said.
Kathleen Craft, shelter coordinator for the city of Livermore, California, said temperatures had reached 99 degrees shortly after midday but only one woman had shown up at the city's cooling center.
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“We’re anticipating we’ll see more people tomorrow when a temperature of 108 degrees is forecast,” Craft said.
The California Independent System Operator, which monitors power lines across the state, issued a flex alert for Thursday night asking residents to avoid energy usage to reduce strain on state power.
Forecasts also showed enough reserves to cover demand Thursday evening but Californians should be vigilant in case there's need for a Flex Alert as solar energy production drops off, it said.
In Texas, the Energy Reliability Council of Texas asekd residents this week to conserve energy to avoid rolling blackouts. Already Monday, power plants had had unexpected outages, losing enough power to darken 2.4 million homes.
“That it happened so early in June, it makes me nervous about what is in store for us, not just later this summer but also in the years ahead," said Virginia Palacios, executive director of Commission Shift, an advocacy group that contends the state should do more to shore up the grid.
Many areas of Texas, such as Dallas and Austin, approached triple-digit temperatures Tuesday.
Dry weather adds new challenge as wildfires rage in Montana, Wyoming
A 107 degree reading in Salt Lake City on Tuesday matched the hottest ever recorded in Utah's capitol, matching previous highs recorded in July 2002 and July 1960.
Tuesday, Denver hit 101 degrees, scorching the daily record set in 1952 and 1993 of 97. Wednesday, the city also hit 100 degrees, making it the 14th time in Denver history the city has had back-to-back 100 degree days, and the earliest days yet.
Also Tuesday, Billings, Montana. rocketed to 108 degrees, tying the city's hottest temperature recorded in 2002. Wednesday, Laramie hit a new record of 92, and Cheyenne tied at 93, records previously set in 2007 and 1940 respectively.
Temperatures in all these states are set to cool down by the weekend. But in Montana, temperatures have made it tougher to fight wildfires that have exploded in size, triggering evacuations and destroying an undetermined number of homes. Furious winds have stoked the flames and forced the crash-landing of a firefighting helicopter.
At least 14 new fires have been reported in Montana and Wyoming since Tuesday.
The dry weather was also being felt in Idaho, where authorities are preparing for what could be a challenging wildfire season.
Nick Nauslar, a meteorologist with the National Interagency Fire Center, told state officials this week that nearly 80% of Idaho is in drought and the rest will likely experience it in the coming months. He said Idaho had its second-driest spring in the last 126 years.
Expect more in the future, say experts
Scientists who study drought and climate change say that people living in the American West can expect to see more of the same in the coming years.
“Heat waves are getting worse in the West because the soil is so dry” from the region's megadrought, said Park Williams, a University of California, Los Angeles, climate and fire scientist who has calculated that soil in the western half of the nation is the driest it has been since 1895. “We could have two, three, four, five of these heat waves before the end of the summer.”
Contributing: Chelsea Curtis, Arizona Republic; Bob Sechler, Austin American Statesman; The Associated Press.