Heat Crisis Ahead: US Hospital Visits Could Double by 2040 as Extreme Temperatures Surge

America Is Running Out of Time to Prepare for Deadly Heat

As another brutal summer approaches, a sobering new study is raising urgent alarms about the long-term consequences of extreme heat across the United States. According to research published in the American Geophysical Union journal GeoHealth, the next 15 years could witness a dramatic surge in heat-related hospitalizations — with the numbers potentially doubling by the year 2040.

Hospitalizations Set to Skyrocket

Researchers project that annual heat-related emergency department visits and hospitalizations will climb from approximately 109,000 cases per year to as many as 237,000 by 2040. That sharp increase would, in turn, drive annual healthcare costs for heat-related conditions to more than $1 billion — nearly double current spending levels.

The findings underscore a growing public health emergency. Extreme heat already claims more American lives each year than every other type of severe weather combined, and heat-related deaths have surged by over 50% during the past two decades alone.

Who Is Most at Risk?

The burden of extreme heat does not fall equally. The study, which analyzed 53 of the country's largest metropolitan areas, found that:

• California and the Las Vegas region are expected to record the highest total number of heat-related health incidents.
• The northeast and Ohio Valley, regions historically unaccustomed to extreme heat, are projected to suffer the most severe health consequences during major heat events.
• Elderly individuals and those with pre-existing health conditions face the greatest danger.
• Lower-income households are disproportionately vulnerable, particularly those unable to afford air conditioning, those working outdoors, or those living in homes not designed to withstand high temperatures.

"Heat is an amplifying event," said Vivek Shandas, a professor at Portland State University and co-author of the study. "If you are already struggling with a pre-existing condition, there's a good chance it will lead to some kind of illness like heatstroke or even death."

A Perfect Storm of Risk Factors

The crisis is being compounded by several converging pressures. The US recorded its hottest March ever this year, and forecasters are warning of above-average summer temperatures alongside a heightened risk of widespread wildfires — consistent with broader climate trends driven by fossil fuel emissions.

At the same time, energy costs are climbing sharply. The average American household is expected to spend close to $800 on electricity this summer, a rise of more than 10% compared to last year, according to a report from the National Energy Assistance Directors Association (NEADA) and the Center for Energy Poverty and Climate.

"When temperatures break records, utility bills often do too," said Mark Wolfe, executive director of NEADA. "For families already struggling to make ends meet, higher cooling costs can force difficult choices between paying utility bills and covering other necessities such as food, rent, or medicine."

Meanwhile, federal support for heat mitigation has been diminishing. The current administration has cut programs designed to help cities manage extreme heat, leaving many municipalities — especially in northern latitudes — without adequate resources or infrastructure.

Cities Are Dangerously Unprepared

Shandas and his co-author Stephan Brown of CAPA Strategies paint a stark picture of a nation ill-equipped for the climate challenges ahead.

"There is a staggering cost to society we are going to see over the next 15 years," Shandas warned. "It's not that we will see a plateau of heat-related illnesses and simply acclimate — there is going to be a sustained increase."

Many cities, particularly those in northern regions, are described as "woefully unprepared" for the escalating threat. Public health agencies are already under pressure, and the rollback of climate-focused interventions is leaving communities exposed.

"It's a moment where a number of trains are heading toward each other on the same track," Shandas said. "The heat risk isn't growing just because of the temperature — it's growing because more vulnerable people are living in places that are experiencing more extreme heat."

The Urgent Need for Action

The message from researchers is clear: without meaningful investment in heat resilience, cooling infrastructure, and support for vulnerable populations, the human and financial toll of extreme heat will only grow. With this summer already shaping up to be another record-breaker, the window for preparation is narrowing fast.