In summary
Inland communities with big population booms will experience the most extreme heat days under climate change projections. The combination puts more people at risk — and many cities are unprepared.
On a recent sunny afternoon in Lancaster, Cassandra Hughes looked for a place to cool down. She set up a lawn chair in the shade at the edge of a park and spent the afternoon with a coloring book, listening to hip-hop music.
Reaching a high of 97 degrees, this August day was pleasant by Lancaster standards — a breeze offered temporary relief. But just the week before, during a brutal heat wave, the high hit 109. For Hughes, the Mojave Desert city has been a dramatic change from the mild weather in El Segundo, the coastal city where she lived before moving in April.
Hughes, a retired nurse, is among the Californians who are moving inland in search of affordable housing and more space. But it comes at a price: dangerous heat driven by climate change, accompanied by sky-high electric bills.
A CalMatters analysis shows that many California cities with the biggest recent population booms are the same places that will experience the most high heat days — a potentially deadly confluence. The combination of a growing population and rising extreme heat will put more people at risk of illnesses and pose a challenge for unprepared local officials.
As greenhouse gasses warm the planet, more people around the globe are experiencing intensifying heat waves and higher temperatures. An international panel of climate scientists recently reported that it is “virtually certain” that “there has been increases in the intensity and duration of heatwaves and in the number of heatwave days at the global scale.”
CalMatters identified the California communities most at risk — the top 1% of the state’s more than 8,000 census tracts that have grown by more than 500 people in recent years and are expected to experience the most intensifying heat under climate change projections.
The results: Lancaster and Palmdale in Los Angeles County; Apple Valley, Victorville and Hesperia in San Bernardino County; Lake Elsinore and Murrieta in Riverside County; and the Central Valley cities of Visalia, Fresno, Clovis and Tulare.
By 2050, neighborhoods in those 11 inland cities are expected to experience 25 or more high heat days every year, according to data from researchers at Scripps Institution of Oceanography, University of Colorado Boulder and UC Berkeley. A high heat day is when an area’s maximum temperature exceeds the top 2% of its historic high — in other words, temperatures that soar above some of the highest levels ever recorded there this century. (The projections were based on an intermediate scenario for future planet-warming emissions.)
Many of these places facing this dangerous combination of worsening heat waves and growing populations are low-income, Latino communities.
“We are seeing much more rapid warming of inland areas that were already hotter to begin with,” said UCLA climate scientist Daniel Swain.
“There’s an extreme contrast between the people who live within 5 to 10 miles of the beach and people who live as little as 20 miles inland,” he said. “It’s these inland areas where we see people who…are killed by this extreme heat or whose lives are at least made miserable.”
While temperatures are projected to rise across the state, neighborhoods along the coast will remain much more temperate.
San Francisco, Santa Barbara and Long Beach, for instance, are not projected to experience significantly more high heat days.
San Francisco will average six days a year in the 2050s exceeding 87 degrees, compared to four days in the 2020s. In contrast, Visalia will jump from 17 days exceeding 103 degrees to 32 — more than a full month.
Unlike the growing inland populations, the cooler coastal counties, — where more than two-thirds of Californians now live — are expected to lose about 1.3 million residents by 2050, according to the California Department of Finance.
High temperatures can be deadly, triggering heat strokes and heart attacks, and exacerbating asthma, diabetes, kidney failure and other illnesses, even some infectious diseases.
Cassandra Hughes sits in the shade in Lancaster on Aug. 15, 2024. The temperature that day reached 97 degrees — cooler than recent heat waves. She strategically cools her home to keep electric bills low. “I have air conditioning, a swamp cooler and two fans,” she said. Photo by Ted Soqui for CalMatters
In California, extreme heat contributed to more than 5,000 hospitalizations and almost 10,600 emergency department visits over the past decade — and the health effects “fall disproportionately on already overburdened” Black people, Latinos and Native Americans, according to a recent state report.
City and county officials must grapple with how to protect residents who already are struggling to stay cool and pay their electric bills. Despite the warnings, many local governments have failed to respond.
A 2015 state law required municipalities to update their general plans, safety plans or hazard mitigation plans to include steps countering the effects of climate change, such as cooling roofs and pavement or urban greening projects.
But only about half of California’s 540 cities and counties had complied with new plans as of last year, according to the environmental nonprofit Climate Resolve.
The California dream or a hellish reality?
An exodus from California’s coastal regions is a decades-long trend, said Eric McGhee, a policy director who researches California demographic changes at the Public Policy Institute of California. People are moving away from the coasts, especially the Los Angeles region and Bay Area, to elsewhere in California and other states.
About 104,000 people moved from the Bay Area to the Sacramento area, the Inland Empire and the San Joaquin Valley in 2021 and 2022, and about 95,000 moved from Los Angeles, Ventura and Orange County to those same inland regions, according to data collected from the Census.
McGhee said most people moving inland are low-income and middle-income Californians looking to expand their families, find cheaper housing and live comfortably — and they’re willing to sacrifice other privileges, like cool weather.
California is “becoming more expensive, more exclusive in the places that are least likely to experience extreme heat,” Swain said. As a result, he said, “the people who are most at risk of extreme heat” — those with limited financial resources — “are precisely the people experiencing extreme heat.”
The San Bernardino County city of Victorville — which is 55% Hispanic and has median incomes far below the state average — is among California’s fastest growing areas, adding more than 12,500 new residents between 2018 and 2022. Nearby Apple Valley and Hesperia grew by about 3,000 and 6,000 people, respectively, while Lancaster, Palmdale and Visalia added between about 10,000 and 12,000.
In Victorville on an August day that reached 97 degrees, Eduardo Ceja wiped sweat from his forehead as he worked at Superior Grocers store, retrieving shopping carts.
The work is often grueling in this Mojave Desert town. He sometimes drinks five bottles of water to stay hydrated as he works, with the concrete parking lot radiating the heat back onto his skin. When he’s done pushing carts, he recovers in the air conditioned store.
The extreme heat “is noticeable. I don’t think there was a day under 100 in July.”
Scott Nassif, apple valley mayor
Ceja, 20, moved to nearby Apple Valley about a year ago, around the same time the new grocery store opened. He used to sleep on his parents’ couch in the San Gabriel Valley town of Covina, east of Los Angeles, which is often more than 10 degrees cooler than Apple Valley on summer days. But he wanted a place to himself at a low cost, so now he pays $400 a month for a bedroom in his brother’s home.
Since he moved here, he’s observed many businesses, including his own employer, expand or open in Apple Valley.
“I notice a lot of people from L.A. are coming here,” he said. It makes sense to him. “Out here, the apartments have more space.”
Apple Valley Mayor Scott Nassif, who has lived there since 1959, said days over 100 degrees used to be rare. Now week-long heat waves above 110 degrees are commonplace. Photo by Ted Soqui for CalMatters
Apple Valley Mayor Scott Nassif has seen his desert town grow and get hotter over his lifetime. When he moved to the area in 1959, only a few thousand people lived there. Now it’s home to more than 75,000 people.
Nassif remembers only a few days that would reach above 100 degrees and multiple snowstorms in the winter. Now, snowstorms are rare, and week-long heat waves above 110 degrees are commonplace.
The extreme heat “is noticeable,” he said. “I don’t think there was a day under 100 in July.”
Nassif attributes the town’s growing population to its good schools, a semi-rural lifestyle and affordable housing for families.
In the high desert town of Hesperia, growth is evident. Banners advertising “New homes!” are posted throughout the town, luring potential buyers to tract home communities. Residents are cautiously eyeing a new development, called the Silverwood Community, that has recently broken ground.
The massive, 9,000-plus acre development is authorized for more than 15,000 new homes, according to its website. A video on its website coaxes potential buyers: “True believers know the California dream is within reach.”
An aerial view of the Silverwood Community, a housing development under construction in Hesperia, on Aug. 16, 2024. The development could include as many as 15,000 new homes to the desert city, which currently is home to about 100,000 people. Photo by Ted Soqui for CalMatters
Hesperia, which is almost two-thirds Hispanic and also has median incomes far below the state average, is anticipating continued growth as housing costs soar in other parts of California. Its planning includes rezoning some areas to allow for higher-density housing, which could bring more affordable housing, said Ryan Leonard, Hesperia’s principal planner.
“If people are willing to make a commute to San Bernardino, Riverside or Ontario — a 45-minute to an hour commute — they can afford to buy a home here when they might not be able to afford that same home down the hill,” Leonard said.
Summer electric bills soar to $500 or more
In the California towns at most risk of intensifying heat, people already are saddled with big power bills because of their reliance on air conditioning.
For instance, households in Lancaster, Palmdale and Apple Valley pay on average $200 to $259 a month for electricity, compared to a $177 average in Southern California Edison’s service area, according to California Public Utilities Commission data as of May, 2023.
In summer months, average power use in these communities nearly triples compared to spring months, so some people’s bills can climb above $500.
And their bills are likely to grow as climate change intensifies heat waves and utility rates rise: Californians are paying about twice as much for electricity than a decade ago. The state’s rates are among the highest in the nation.
“You can’t not run the air conditioner all day… You wouldn’t survive otherwise. The heat is too oppressive.”
Diane Carlson, palmdale resident
Diane Carlson moved to Palmdale, north of Los Angeles, 30 years ago. The housing was much cheaper and she wanted to move where her children could attend school near where they live.
Over the years, she’s felt the temperatures in Palmdale rise.
Carlson said her electric bill during the summers used to average about $500, a significant chunk of her household budget. About four years ago, though, she had solar panels installed on their home, which cut her bill in half.
“You can’t not run the air conditioner all day, even if you run it low,” she said. “You wouldn’t survive otherwise. The heat is too oppressive.”
With multiple days in the summer reaching at least 115 degrees, Carlson is conscious that there may be a future where Palmdale isn’t livable for her anymore.
“Will it get as hot as Death Valley?” she wondered.
Death Valley, the hottest place on Earth, reached record temperatures in July, averaging 108.5 degrees; the high was 121.9, tying a 1917 record. In comparison, Palmdale by 2050 is projected to have 25 days where the maximum temperature exceeds 105, up from nine days in the 2010s.
Carlson said she’d consider moving to the East Coast, where she’s originally from. But she’d face hurricanes rather than the heat. It all comes down to making a decision: “Which negatives are you willing to deal with?”
A street vendor sells fans and mini pools in the Los Angeles County desert town of Lancaster on Aug. 15, 2024. Photo by Ted Soqui for CalMatters
First: An infrared thermometer In Lancaster shows the street surface temperature reached 137 degrees on Aug. 15, 2024. Last: A wire sculpture on a light pole as the hot desert sun shines. Photos by Ted Soqui for CalMatters
Hughes, who lives in subsidized housing in Lancaster, said surviving the heat means constantly checking the weather forecast and strategically cooling her home to keep electricity costs low. “I have air conditioning, a swamp cooler and two fans,” she said.
On a day when the temperature doesn’t reach triple digits, the air conditioner might stay off; she opens the windows and turns on the fans instead.
Local leaders say they know more must be done to protect their residents.
Lancaster opens cooling centers in libraries for residents who need respite from the heat. During heat waves, residents ride buses for free, and city programs provide water and other resources to homeless people.
“Is it adequate? Of course it’s not adequate,” said Mayor R. Rex Parris. “If you’ve got people who don’t read or don’t get a newspaper sitting in a sweltering apartment, the information is not getting to them and we know it.”
Parris said air conditioning is necessary for families to stay cool in the hot desert summers, but with utility costs so high, it’s becoming a luxury.
With that in mind, he said the city is prioritizing hydrogen energy, which could lower electric bills in the long-term. A new housing tract will be powered by solar panels and batteries that store power, backed up by hydrogen fuel cells, which will be cheaper than if the homes drew energy entirely from the grid, said Jason Caudl, head of Lancaster Energy.
Nassif, the Apple Valley mayor, said his town helps residents finance costly rooftop solar panels that can cut their power bills.
“Educating our public on how to save on their electric bills is a big thing, because you can’t live up here without air conditioning,” Nassif said.
Cooling centers aren’t enough to protect people
On a Saturday morning in Visalia, as temperatures climbed to 99 degrees, Maribel Jimenez brought her 2-year-old son to an indoor playground to beat the heat. She sat at a kid-sized table with her son, Mateo, as he played with toy screws and blocks.
Jimenez, 33, has lived in Visalia her whole life. She grew up on a dairy farm and remembers playing outdoors for hours in the summers. But things have changed. She can’t imagine letting her son play outdoors under the scorching sun. She worries he’s not getting the outdoor playtime he should be getting.
“It’s definitely gotten much hotter,” Jimenez said. “You can’t even have your kids outside. We want to take him out to the playground but it’s too hot. By the time it cools down in the evening, it’s his bedtime.”
Other times, she and her family go to the mall for walks, or anywhere where there’s air conditioning.
“As long as he’s out, he’s happy,” she said. “We try our best to protect him.”
Maribel Jimenez and Oscar Olmedo play with their son Mateo in the shade at the ImagineU Children’s Museum in Visalia on Aug. 17, 2024. They say they have trouble finding places where their son can cool off on hot summer days. Photo by Larry Valenzuela, CalMatters/CatchLight Local
The effects of extreme heat on the body can happen quickly and can affect people of all ages and health conditions. Once symptoms of heat stroke begin — increased heart rate and a change in mental status — cooling off within 30 minutes is crucial to survival, said Tomás Aragón, director of the California Department of Public Health
Many municipalities react to extreme heat by following state or county rules, which often involve opening cooling centers in public places when temperatures rise above a certain level for multiple days in a row.
“You want people to be in a space where your body can control its core temperature,” Aragón said. “It’s safer to be in an air conditioned place (that) cools your body down. That’s what cooling centers are for. I tell people, go to the supermarket, go to the library, go to a cooling center, go and just let your body cool down.”
“It’s not just about preventing deaths and other terrible outcomes of heat waves … It’s really about having livable communities where kids can play outside and street vendors can run their businesses without risk of overexposure.”
Ali Frazzini, los angeles county’s Chief Sustainability office
But community advocates say cooling centers are ineffective because they’re underused. Many people are unaware of them, and others have no transportation to reach them.
“I think everyone is used to that being the answer for what we do when it gets extremely hot,” said Jonathan Parfrey, executive director of Climate Resolve. “We need to expand our imagination to figure out other ways of taking care of people.”
Victorville has complied with the 2015 state law requiring plans to handle climate change, and Hesperia is in the process of updating its plans.
But Los Angeles County is an example of a local government that has gone above and beyond to comply, Parfrey said.
The county has updated its emergency preparedness plans and is in the early phases of developing a heat-specific plan for unincorporated areas, which will include urban greening and changes to the built environment to make neighborhoods cooler, said Ali Frazzini, policy director at the county’s Chief Sustainability office.
Families play in the water park area of Adventure Park to cool off in Visalia on Aug. 17, 2024. Photo by Larry Valenzuela, CalMatters/CatchLight Local
“It’s not just about preventing deaths and other terrible outcomes of heat waves, although that’s extremely important,” Frazzini said. “It’s really about having livable communities where kids can play outside and street vendors can run their businesses without risk of overexposure.”
Parfrey said the state plays a role, but “they’re not in charge of the roads or building codes or where you put a water fountain or how you build a local park. All of that has to be done at a local level.”
In 2022, the Newsom administration issued an Extreme Heat Action Plan outlining state steps to make California more resilient to extreme heat. That includes funding new community resilience centers where people can cool down as well as find resources or shelter during other emergencies, such as wildfires. It’s a model that some community advocates prefer over traditional cooling centers that are underutilized.
The state has granted almost $98 million for 24 projects so far, said Anna Jane Jones, who leads development of the centers for the state’s Strategic Growth Council.
“It’s definitely gotten much hotter. You can’t even have your kids outside. We want to take him out to the playground but it’s too hot.”
Maribel Jimenez, Visalia resident
In Visalia, Jimenez said her family doesn’t have many options for cool spaces where her young son can be entertained.
At home, the family uses the air conditioner sparingly and keeps the blinds closed. During a heat wave, their power bill can climb to $250. If the bills were lower, she’d use the air conditioner all the time “We have to do what we have to do,” she said.
Jimenez and her husband have thought twice about expanding their family and have floated the idea of moving somewhere else, but many of the affordable options, like Texas or Arizona, are even hotter than Visalia.
“Global warming is a thing, and the heat isn’t getting any better anytime soon,” she said. “Everybody’s paying the price.”