A fierce heatwave has shattered temperature records across the US west and has been tied to at least four deaths in Oregon, with more heat on the way as dangerous weather fueled the outbreak of new wildfires.
Oregon faced triple-digit temperatures and saw several records toppled over the weekend, including in Salem, where on Sunday it hit 103F (39.4C), topping the 99F (37.2C) mark set in 1960. Authorities in Multnomah county – home to Portland, where temperatures broke daily records over the weekend – said they were investigating four suspected deaths tied to the heatwave.
More than 146 million Americans were under extreme heat alerts on Monday, as both sides of the country cooked. Excessive heat warnings, the National Weather Service’s (NWS) highest alert, stretch across the west, covering parts of California, Nevada, Arizona, Oregon, Washington and Idaho. Areas on the east coast, including Florida, Georgia, Alabama and Mississippi, were also under heat advisories.
Dozens of locations in the west and Pacific north-west tied or broke previous heat records in recent days. On Sunday, Las Vegas set an all-time record high of 120F (48.8C), while across the desert in Death Valley national park, temperatures reached 128F (53.3 C), breaking a daily heat record and coming just shy of its all-time high. The dangerous temperatures caused the death of a motorcyclist in the park.
Meanwhile, firefighters are battling a flurry of new blazes that sparked in the brutal temperatures over the weekend, with the sweltering conditions posing challenges for fire crews. There were 73 large active fires burning across the country on Monday, according to the National Interagency Fire Center, collectively covering close to half a million acres, and fire conditions are expected to continue through the week.
California, which was left covered in quick-to-burn grasses after a wet winter, saw an explosive week, and firefighters are battling 18 active blazes.
In Santa Barbara county, the Lake fire burned through dry grass, brush and timber over the weekend, prompting evacuations of some rural homes, including the Neverland ranch. The fire has grown to 20,320 acres and was at 8% containment Monday morning.
Further north, the Shelly fire, which erupted in California’s Marble Mountain Wilderness last Wednesday, continues to pose threats to “communities, private timberlands, cultural resources, and wilderness areas”, Cal Fire posted in an update Monday, as fire behavior became more extreme through the weekend.
“Yesterday, as well as today, we have experienced some problematic weather forecasts that leads to critical fire behavior,” John Chester, operations section chief with Cal Fire’s Siskiyou unit said. “We are expecting the same weather patterns and forecasts over the next few days.”
Fire conditions have also been intense in Utah, fueling rapid growth for several large fires.
The Silver King fire, which has roared across more than 10,823 acres – more than 4,500 acres in a single day – has exhibited extreme behavior and is 0% contained. Hundreds of homes are at risk from the fire, as state officials secured federal support Monday.
“A warming and drying trend will continue today with an excessive heat warning, as temperatures continue to increase above average the relativity humidity continues to drop to 10 – 15%,” officials with the US Forest Service said in a Monday morning update on the fire, adding that gusty winds will continue to fan the flames. “These elements combine for extreme fire weather.”
The heatwave came as the global temperature in June hit a record high for the 13th straight month and it marked the 12th straight month that the world was 1.5C (2.7F) warmer than pre-industrial times, the European climate service Copernicus said.
While parts of California will see some relief from the brutally hot conditions, extreme heat is predicted to linger across the US west throughout the week. As the heatwave shifts north into Oregon and Washington, and moves east covering parts of the Great Basin and Arizona, more records will likely be broken.
“The multi-day length and record warm overnight temperatures will continue to cause heat stress in people without adequate cooling and hydration,” NWS meteorologists wrote in a forecast published on Monday.
Rare heat advisories were extended even into higher elevations including around Lake Tahoe, on the border of California and Nevada, with the weather service in Reno, Nevada, warning of “major heat risk impacts, even in the mountains”.
More extreme highs are in the near forecast, including possibly 130F (54.4C) around midweek at Furnace Creek, California, in Death Valley. The hottest temperature ever officially recorded on Earth was 134F (56.67C) in July 1913 in Death Valley, though some experts dispute that measurement and say the real record was 130F (54.4C), recorded there in July 2021.
Park officials warned visitors to take the heat seriously. “While this is a very exciting time to experience potential world record-setting temperatures in Death Valley, we encourage visitors to choose their activities carefully, avoiding prolonged periods of time outside of an air-conditioned vehicle or building when temperatures are this high,” Mike Reynolds, a park superintendent said.
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