US heatwave smashes records as ‘extreme fire weather’ fuels new blazes Over 146 million Americans under extreme heat alerts as dozens of locations in US west tie or break past heat records

 

The Lake Fire burns close to what was Michael Jackson's Neverland Ranch in Los Olivos, California, on 6 July 2024. Photograph: David Swanson/Reuters

A fierce heatwave that shattered records this weekend – with dangerous temperatures that spiked well into the triple digits – will continue to grip much of the US in the coming days and fuel fires across the west.

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 it’s all time high. The dangerous temperatures caused the death of a motorcyclist in the park.

Oregon also faced triple-digit temperatures and saw several records toppled, 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, said they were investigating four suspected deaths tied to the heatwave.

Meanwhile, firefighters are battling a flurry of new blazes that sparked in the brutal temperatures over the weekend, with the sweltering, dry conditions posing challenges for fire crews. There were 73 large active fires burning across the country 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 on 3 July, continues to pose threats to “communities, private timberlands, cultural resources, and wilderness areas”, CalFire 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 CalFire’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 heat wave 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.

 People shield their eyes from the sun along the Las Vegas Strip on Sunday, when the city set an all-time record high temperature of 120F (48.8C). Photograph: John Locher/AP

 

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.