A heat dome is on tap for the West. Here’s what to know

The outline of six people is seen against a red sky and bright yellow sun.
A blazing sun silhouettes visitors to Signal Hill during a heat wave in September 2022.
(Luis Sinco / Los Angeles Times)
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Good morning. It’s Monday, June 3. Here’s what you need to know to start your day.

What to know about the West’s impending heat wave

It’s been a mild to cool spring for much of California, but parts of the state are set to get an early dose of summery temperatures.

Forecasters say a heat dome will bring higher-than-usual temperatures to the Golden State by midweek.

Higher temperatures could stick around California for up to 14 days. The heat dome, which could produce life-threatening conditions in some regions, is also expected to reach the Pacific Northwest and southwestern Canada.


That lingering heat “could break records, prime the landscape for wildfires and kick off a sizzling summer,” L.A. Times environment reporter Hayley Smith writes.

“Though California has enjoyed two relatively tame fire seasons thanks to back-to-back wet winters,” she reported, “it has seen an explosion of new vegetation that can be cured by the incoming heat, creating fuel for future flames.”

How hot is it expected to get — and where?

Portions of Northern California and the Sierra Nevada foothills are expected to bear the brunt, according to UCLA climate scientist Daniel Swain.

Large parts of the Sacramento Valley could experience triple-digit temperatures, with some areas exceeding 110 degrees by midweek. The Central Valley is under an excessive heat watch.

“This will be another event where a fair chunk of California’s population — the near-coastal dwellers in the Bay Area and in Southern California — probably won’t see extreme heat,” Swain said during a media briefing last week. “But you might not have to go that far inland to see dramatically hotter temperatures. And if you go far enough inland, you might even see record-breaking heat.”


Forecasters note that this may be a teaser for a long, sweltering summer.

NOAA’s latest seasonal temperature outlook points to above-normal temperatures in June, July and August across most of the U.S.

It’s not just standard summer heat

Yes, the mercury rises in summertime. But experts note that hotter-than-normal conditions expected over the next few months are being driven by two key factors: changes in the El Niño-La Niña cycle and climate change.

The Pacific climate pattern El Niño has weakened but continues to warm tropical waters, which drive heat waves and other atmospheric patterns.

But El Niño cycles are occurring on a warming globe, courtesy of our continued burning of fossil fuels, which is making heat waves more frequent, prolonged and lethal.

Hayley wrote a detailed explainer on how climate change is affecting heat waves in the Golden State and beyond — and what we can expect if current emissions continue unabated.


“Although California and the American West will continue to experience cool days and periods of heavy snowpack, scientists say the long-term trend is for the planet to grow hotter with the continued burning of fossil fuels,” she wrote. “Since 1880, the global average temperature has increased by about 2 degrees.”

More intense heat waves, more deaths

The potential for record-breaking and sustained summer heat exposes millions to heat-related illnesses and death.

An analysis by the Associated Press found that last year’s summer heat killed more than 2,300 people in the U.S., a record. That figure is likely a major undercount, dozens of experts told AP reporters. Heat kills more people each year than hurricanes, floods and wildfires.

A heat wave in 2022 killed an estimated 395 people in California, according to state health officials.

Extreme heat disproportionately affects children and the elderly, people with chronic illnesses, disabled people and those who are pregnant. It also has a greater impact on people who work predominantly outdoors, such as construction workers, landscapers and agricultural workers.


California has struggled to keep up with the dangers of extreme heat, which is intensifying due to human-caused climate change. Gov. Gavin Newsom launched the Extreme Heat Action Plan in 2022, which states that a proper response to the hazards posed by deadly heat “will require time, effort and funding.”

But state leaders plan to slash funding for the Extreme Heat and Community Resilience Program by more than 60%. According to a state Assembly committee summary from May, the program would lose $110.1 million of its $175-million allotment.

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Exposed tufa towers along the shore of Mono Lake in Lee Vining, Calif.
(Brian van der Brug / Los Angeles Times)

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Commentary and opinions


Today’s great reads

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A flooded road in the San Joaquin Valley in April 2023.
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California has underestimated the epic potential of future flooding, research shows. Looks like our “Great Flood” wasn’t actually our most devastating. Researchers found evidence of two epic Southern California floods that occurred in the last 600 years and were much larger than the Great Flood of 1862.

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For your downtime

Artwork of a woman in a floral dress leaning back on a colorful couch.
Mickalene Thomas, “Afro Goddess Looking Forward,” 2015, rhinestones, acrylic and oil on wood panel.
(© Mickalene Thomas)

Going out

Staying in


And finally ... a great photo

Show us your favorite place in California! We’re running low on submissions. Send us photos that scream California and we may feature them in an edition of Essential California.

A black and white photo shows a kiosk within a cavernous, tiled space.
The illuminated (and possibly illuminating) information desk at Los Angeles’ Union Station.
(Robert Gideon)

Today’s great photo is from Los Angeles resident Robert Gideon: the L.A. staple that is Union Station.

Robert writes: “The awe-inspiring vaulted ceilings, marble and old wood framing in the original ticketing area ... speak to another era of grandeur that is representative of Downtown L.A.’s historic early 20th century period. The historic ticket counters in the background have long since been replaced, but the information desk is still very active.”

Have a great day, from the Essential California team

Ryan Fonseca, reporter
Amy Hubbard, deputy editor, Fast Break

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