- Written by Nadine Youssef and Christy Cooney
- BBC News, Toronto and London
Parts of the US are expected to see record temperatures on Sunday, with warnings of “dangerous” heat levels next week across the Southwest.
Nearly a third of Americans — about 113 million people — are currently under heat warnings, from Florida to California to Washington state.
The country's National Weather Service urged people not to underestimate the life-threatening risks.
On Saturday, a sweltering temperature of 118 degrees Fahrenheit (48 degrees Celsius) was recorded in Phoenix, Arizona.
This means temperatures reached 110 degrees Fahrenheit (43 degrees Celsius) for 16 days in a row, an almost record high.
Mobile clinics there reported treating homeless people suffering from third-degree burns.
Meanwhile, temperatures in California's Death Valley – one of the hottest places in the world – are expected to reach 129 degrees Fahrenheit (54 degrees Celsius), approaching the highest temperatures ever recorded on Earth.
Local records could also be set Sunday in the San Joaquin Valley, Mojave Desert and Great Basin areas, the NWS said.
Its update Saturday evening said the temperatures “will pose a health risk and may be fatal to anyone without effective cooling and/or proper hydration.”
It is estimated that about 700 people die each year from heat-related causes in the United States, according to the Centers for Disease Control and Prevention (CDC).
In neighboring Canada, officials say wildfires sparked by above-average temperatures — which have blanketed parts of the United States in smoke — have now burned nearly 10 million hectares (25 million acres) of land.
The National Weather Service said earlier that the temperatures in the American Southwest are the result of a series of high pressure in the upper level, which usually brings with it warmer temperatures, adding that the heat wave was “one of the strongest” systems of its kind to hit the world. . region.
The temperature in Las Vegas, Nevada, could also reach an all-time high of 117 degrees F (47 degrees C) in the next few days.
Meteorological officials warned locals who thought they could handle the temperatures that this was “not typical desert heat.”
“It's the desert, of course it's hot – that's a dangerous mentality!” the NWS in Las Vegas tweeted.
“This heat wave is not typical desert heat due to its long duration, extreme daytime temperatures, and warm nights. Everyone should take this heat seriously, including those who live in the desert.”
The National Weather Service also warned of the potential for strong to severe thunderstorms, heavy rain and flooding in several locations, including the New England Northeast region.
Parts of the southwestern United States have already faced sweltering temperatures over the past week. In El Paso, Texas, temperatures reached the Fahrenheit numbers for 27 consecutive days.
Air conditioning use in the state has surpassed the previous record for energy consumption as people try to stay cool, while parks, museums and zoos have closed or reduced their operating hours.
Hospitals were also seeing heat-related admissions.
“We're having a lot of heat-related illnesses now, a lot of dehydration and heat exhaustion,” said Dr. Ashkan Morem, who works in the emergency room at Dignity Health Siena Hospital, outside Las Vegas.
Overnight temperatures are expected to remain “abnormally warm” in some areas, offering little overnight relief from the heat.
The US heat wave mirrors similar scorching conditions in Europe, which forced Greece to close one of its main tourist attractions, the Acropolis, on Friday and Saturday.
The first week of July saw an average global temperature of 63 F (17.23 C), according to the United Nations, the highest ever recorded.
Scientists say the temperatures are driven by climate change and a natural weather pattern known as El Niño, which occurs every three to seven years and causes temperatures to rise.
The world has already warmed by about 1.1°C since the beginning of the industrial age, and temperatures will continue to rise unless governments around the world make sharp cuts in emissions.
Speaking to the BBC, Paolo Sepe, a lecturer in climate science at Imperial College London, said that rising global temperatures undoubtedly contribute to an increase in extreme weather events.
“Of course it's not unusual to have a heat wave in the summer, per se, but what has become really unusual is the clustering of heat waves,” he said.
“We have this event in southern Europe, but at the same time, we're having another big heatwave in the southern US. And recently, we've had heatwaves in South Asia, India, China, etc. Unfortunately, that's not surprising.
“We have core temperatures that are shifting higher, so you shift the probabilities toward more intense extreme events, and fewer cold extreme events.”
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