Valerie Brown remembers being so hot during the 1995 Chicago heat wave that she got up in the middle of the night, took a cold shower in her T-shirt, plopped onto her bed soaking wet and fell back asleep.

When she woke up that morning in July 1995, the heat was still brutal, and she called her grandmother, Alberta, who lived nearby, to see how she was faring.

“She didn’t answer the phone, and she was the stereotypical grandma who always answers,” Brown said.

When Brown’s sister went to check, she found their grandmother dead in her home, the windows all shut. The heat killed Alberta and 738 other people in Chicago over five days in July.

Chicago residents told stories of bodies piling up on the streets as city officials weren't prepared to handle the large volume of deaths.

“They put my grandma’s body in a refrigerated truck,” Brown said. “There is no death certificate. They just took her body away and put her in a mass grave.”

The death toll from the ’95 heat wave was shocking and “raised the consciousness of everyone in the city,” Aaron Bernstein, co-director of the Center for Climate, Health and the Global Environment at Harvard’s T.H. Chan School of Public Health, said. Bernstein grew up in Chicago, and remembers his grandmother thanking god for air-conditioning that summer.

“Heat waves aren’t just uncomfortable,” he said. “They’re deadly.”

As cities on the East Coast and in the Midwest prepared for this weekend's heat wave, where around 200 million Americans are under excessive heat warnings, many of the measures that cities are taking were born in the wake of the ’95 heat wave. But the problems and inequities that caused those deaths still remain.

“Evidence is clear that people who are in the Medicare population are at increased risk for getting hospitalized and dying during a heat wave,” Bernstein said. Also at risk: infants, people with heart failure, kidney disease, or chronic lung disease, pregnant woman, and the poor. While there have always been heat waves, Bernstein said the problem now is that, with climate change, extreme heat is more common and more severe.

When a heat wave is forecast, cities treat them like a short-term emergency. New York, Boston and Chicago are opening cooling centers, extending community center hours, sending alerts warning residents of the impending heat, and telling people to stay in air-conditioning as much as possible.

These are helpful measures that keep many cool, hydrated and safe. But they don’t reach everyone. “You see increases in people dying before the heat alert actually happens,” Bernstein said. Even more, the alerts often don’t reach the city’s most vulnerable populations. People most at risk, like the elderly, poor and socially isolated, are less likely to have access to the internet or the news, and may not be receiving the messages.

“Cooling centers are helpful, but a lot of people aren’t getting to them,” Bernstein said.

Judith Helfand, director of “Cooked: Survival by Zip Code,” a new documentary about the 1995 Chicago heat wave, said cities like Chicago treat cooling centers as a Band-Aid for a much larger and unaddressed problem that determines who lives and dies in the heat: structural racism.

“The people who died in 1995 were poor, and disproportionately black,” Helfand said. In some black communities that had faced decades of disinvestment, residents didn’t have stores, shops, movie theaters or community centers to retreat to in the heat. As wealthy white residents on Chicago’s North Side stayed in their air-conditioning or fled to summer homes, Helfand said, residents on the South Side were suffocating in their own homes.

Now, libraries, schools and police stations function as cooling centers, but what happens if your city has been shutting down libraries and schools and you don’t feel comfortable going to the police station?

These are questions, Helfand says, that heat wave planners don’t ask enough. “The best heat emergency plan is built around community-based organizations and community-based anchor institutions who are operating and working everyday to address inequity, disparity and structural racism,” Helfand said. She calls such organizations and institutions “everyday cooling centers.”

“Racism kills people,” she said, but nobody calls it an emergency.

The homeless are also particularly at-risk during heat waves. They often die, Bernstein said, after becoming trapped on hot pavement as cities become “urban heat islands.”

And at the same time, new research shows that if the global average temperature rises three degrees Celsius above pre-industrial levels, a major heat wave could kill almost 6,000 people in New York City. Similar events could kill more than 2,500 in Los Angeles and more than 2,300 in Miami.

Experts say that as Americans brace for this weekend’s heat wave, and as such waves become more common because of climate change, what will be an inconvenience for those with resources could prove dangerous for those without. Heat waves, they say, highlight real problems that are endemic and systemic to our society.

“One of the things that’s so critical about the health impacts of climate change is that these are not equal opportunity killers,” Bernstein said, adding heat waves hurt the people who “we already need to help the most.”

As we look toward this weekend and what’s in store for the future, Linda Rae Murray, a professor of public health at the University of Illinois at Chicago, said we need a “whole different societal approach to these weather events.”

“If we build cities and make resources available on a sense of equity, then it’s possible for communities to adjust and prepare for extreme weather events that are becoming the new normal,” she said.

Until then, Murray says it’s going to be poor people and people of color who face the brunt of the ever-growing presence of extreme weather events like heat waves.

“The 1995 heat wave was not a one-time disaster,” Murray said. “We are creating a new normal.”