A New Dangerous Heat Wave Is Coming for the U.S. (Yes, Another One)

A New Dangerous Heat Wave Is Coming for the U.S. (Yes, Another One)
It's becoming all too familiar. (Screenshot: Earth Wind Map)

The U.S. West Coast can’t catch a break from dangerous and extreme heat. A new heatwave is set to hit the region this weekend. The Northwest will, thankfully, be spared the worst of the heat. But sizzling temperatures will spread across a large area that includes the entire West Coast and portions of the Northern Rockies and Southwest. Abnormally hot temperatures will even spread as far north as Nunavut in Canada.

Ahead of the heat, the U.S. National Weather Service issued excessive heat warnings for much of Northern and Central California beginning Friday and lasting through the weekend. The heat could also make it harder to fight the growing wildfires in British Columbia tied with last week’s record-smashing heat, in what is shaping up to be a relentless summer across the West.

California and Nevada Will Be the Heat Epicentre

In terms of absolute high temperatures, California could see the worst of the heat. The NWS forecast highs will easily clear 37.8 degrees Celsius for several cities and could challenge daily, monthly, or even all-time records.

To get a taste of the searing heat: California’s Death Valley could see temperatures reach 54.4 degrees Celsius, which would tie the hottest temperature ever reliably recorded on Earth set in the same locale just last year. While that’s the most extreme forecast high, more populated locations won’t be spared from shockingly hot weather either.

In Las Vegas, highs could tie or surpass the city’s all-time record of 47 degrees Celsius this weekend. The Sacramento Valley could hit 46.1 degrees Celsius, the Central Valley could see 45 degrees Celsius and inland Southern California could reach 47.2 degrees Celsius. NWS has issued a heat risk forecast for the Central Valley warning that temperatures like this “happens rarely.” Largely portions of the region are at a level 4 warning due to the long-term duration of hot temperatures.

“Expect little overnight cooling,” the alert continues. “This is a multi-day excessive heat event.”

The Heat Will Worsen Drought and Strain the Grid

More than 90% of the West is in drought, according to the Drought Monitor, and the heat will make matter worse by further drying out the soil and evaporating limited water supplies from reservoirs.

On Thursday, U.S. Gov. Gavin Newsom added nine counties to the state’s drought declaration — making 50 of California’s 58 counties officially in emergency drought conditions — and asked that residents try and curb their water use by 15%. The state’s reservoirs have already shrunk rapidly following repeated bouts of heat earlier this year and below-average snowfall. That’s had gnarly impacts from making water taste like dirt to putting hydropower at risk.

Speaking of, power could be in short supply as people rush to crank up air conditioning when the heat hits. California grid operators have already asked residents to save electricity in order to prevent outages. PG&E, the largest utility in California, said it may implement shutoffs to prevent wildfires as well, following a trend in recent years. (Five of the 10 most destructive wildfires in California over the past six years have been linked to the company and faulty equipment or downed wires.)

Heat Warnings Extend Across the Border, Too

Because extreme weather knows no bounds, the heat will extend to Canada, too. Parts of British Columbia, Alberta, Saskatchewan, Manitoba, and the Northwest Territories are under heat warnings. Temperatures could cross 26.7 degrees Celsius above the Arctic Circle. Not quite as dramatic as 54.5 degrees Celsius sure, but not exactly normal for the region.

Temperatures are forecast to 31 degrees Celsius in the eastern corner of British Columbia where heat will mix with smoke to create dangerous conditions for public health.

This Is What the Climate Crisis Looks Like

The devastating heat wave that hit the West Coast at the end of last month was unusual in that the pressure centred over the Pacific Northwest, a region that doesn’t usually see extreme temperatures. The lack of air conditioning coupled with relentless heat contributed to widespread deaths. It will take weeks or even months to grasp the full toll, but officials in Oregon have declared the heat wave a “mass casualty event.”

A snap analysis using peer-reviewed techniques released this week found that the last heat wave would have been “virtually impossible” without climate change. The same is almost certainly true for the heat coming this weekend, with scientists beginning to operate under the assumption that the climate crisis is playing a role in all heat waves by either making them more likely or intense.

“We believe that California is very clearly experiencing the impacts of a changing environment,” Brian Ferguson, deputy director of crisis communications for the California Office of Emergency Services, told the New York Times. “We’re seeing drought conditions we haven’t seen before, and there is a cascading impact, but it really all comes back to climate.”