How Better Weather Forecasts Could Cut Heat Deaths as Climate Warms

It’s a Tuesday afternoon in late April 2026, and the thermometer outside your window in Phoenix, Arizona, is already creeping toward 95°F. By tomorrow, the National Weather Service is predicting 102°F—a temperature that, while not unprecedented here, carries a silent threat. For years, residents of the Valley of the Sun have relied on weather forecasts to decide whether to cancel outdoor work, adjust irrigation schedules, or even postpone a morning run. But what if those forecasts could do more than just guide your wardrobe choices? What if they could literally save lives?

New research from the University of Arizona suggests that improving the accuracy of short-term weather forecasts could reduce heat-related deaths in the U.S. By 18% to 25% by the year 2100. For a city like Phoenix—where extreme heat already claims more lives annually than hurricanes, floods, or wildfires combined—those numbers aren’t just statistics. They’re a roadmap for survival in a climate that’s only getting hotter.

The Science Behind the Forecast

Derek Lemoine, an economics professor at the University of Arizona’s Eller College of Management, led a team of researchers from Columbia University, the University of Oregon, and Princeton University to tackle a question that’s as much about human behavior as it is about meteorology: Can better weather forecasts actually reduce mortality during extreme heat events?

Their answer, published in the journal PNAS, is a resounding yes. The team analyzed day-ahead National Weather Service forecasts across the contiguous U.S. Dating back to the summer of 2004, cross-referencing them with actual weather data from Oregon State University’s PRISM Climate Group and county-level mortality records from the Centers for Disease Control and Prevention. What they found was striking: the greatest risk of heat-related death occurred when forecasts underestimated hot conditions. In other words, when the weather turned out to be hotter than predicted, people were caught off guard—and the consequences were often fatal.

Lemoine’s team didn’t stop at historical data. They likewise surveyed professional meteorologists in early 2025 to project how forecasting technology might evolve in the coming decades. The results informed three future scenarios: one where forecast accuracy improves in line with meteorologists’ most optimistic expectations, another where it stagnates or declines, and a third where predictions become perfectly accurate. When they modeled these scenarios against different climate warming projections—ranging from 1.6°C to a catastrophic 3.8°C—they discovered something remarkable. In several cases, improved forecasting could offset the projected increase in heat-related deaths caused by climate change.

“That could offset the extra heat-related deaths caused by climate change,” Lemoine said. “To be clear, we would still rather not experience the climate change—but at least we can find ways to potentially cancel out the increased mortality.”

Why Phoenix Is Ground Zero for This Research

Phoenix isn’t just a case study in this research—it’s a city where the stakes couldn’t be higher. In 2023, Maricopa County reported 645 heat-associated deaths, a record that shattered the previous year’s total by nearly 50%. The city’s urban heat island effect, where concrete and asphalt absorb and re-radiate heat, can make temperatures in some neighborhoods 10°F hotter than in surrounding areas. And with climate models predicting that the number of days above 110°F in Phoenix could double by 2050, the need for accurate forecasts isn’t just about comfort—it’s about survival.

But Phoenix also offers a unique lens through which to view this research. The city is home to the National Weather Service’s Phoenix Forecast Office, one of the most advanced in the country, and Arizona State University’s School of Sustainability, which has been studying urban heat mitigation for decades. Local initiatives like the Phoenix Heat Action Plan already rely on weather forecasts to trigger cooling center openings, distribute water to homeless populations, and issue heat advisories. The question now is whether those forecasts can become precise enough to save even more lives.

Capture, for example, the difference between a forecast predicting 105°F and one predicting 112°F. To the average person, that might seem like a minor discrepancy. But for outdoor laborers, elderly residents, or those without access to air conditioning, that 7-degree difference could mean the difference between taking precautions and facing heatstroke. Lemoine’s research suggests that as climate change increases the frequency of extreme heat events, the value of accurate forecasts will only grow—and the cost of inaccurate ones will become even more deadly.

The Economic Case for Better Forecasts

Lemoine’s background in economics adds another layer to this conversation. Governments routinely conduct cost-benefit analyses for new policies, and a key part of that process is assigning a value to lives saved. The U.S. Department of Transportation, for instance, uses a figure of roughly $11.6 million per statistical life when evaluating safety regulations. When Lemoine and his team applied similar metrics to their findings, they discovered that the economic value of improved forecasting is staggering.

“Economists aren’t valuing life itself,” Lemoine explained. “We’re valuing reductions in the risk of dying. The government conducts a cost-benefit analysis of new policies, and a key part of that involves assigning a standardized value to any lives saved. That value is so large that it often dominates the analysis.”

In practical terms, In other words that investing in better forecasting technology—whether through improved satellite data, AI-driven prediction models, or expanded weather station networks—could pay for itself many times over in lives saved and healthcare costs avoided. For a city like Phoenix, where heat-related hospitalizations already strain emergency rooms every summer, the case for prioritizing forecast accuracy is as much about public health as it is about economics.

The Human Factor: Who’s Most at Risk?

Not everyone in Phoenix faces the same risk from extreme heat. The city’s most vulnerable populations—outdoor workers, the elderly, low-income residents without air conditioning, and the homeless—are disproportionately affected. The Maricopa County Heat Vulnerability Index, developed by local public health officials, maps these risks down to the neighborhood level. Areas like South Phoenix, where tree cover is sparse and poverty rates are high, often experience the most severe heat impacts.

This is where the intersection of forecasting and public policy becomes critical. If a forecast predicts a dangerous heat day, city officials can utilize that information to activate cooling centers, deploy mobile hydration units, and issue targeted warnings to at-risk communities. But if the forecast is inaccurate—if it underestimates the heat—those measures may not be enough. Lemoine’s research underscores the importance of not just having forecasts, but ensuring they’re as precise as possible.

It’s also a reminder that technology alone won’t solve the problem. Even the most accurate forecast is useless if people don’t act on it. That’s why cities like Phoenix are increasingly pairing forecasting improvements with public education campaigns. Programs like the HeatReady initiative, run by Arizona State University, teach residents how to recognize the signs of heat exhaustion, stay hydrated, and check on vulnerable neighbors. When combined with better forecasts, these efforts could create a powerful feedback loop: more accurate predictions lead to more effective warnings, which lead to more lives saved.

What’s Next for Phoenix—and Beyond

So where does Phoenix go from here? The city is already taking steps to address the heat crisis, from planting more trees to expanding its network of cooling centers. But Lemoine’s research suggests that investing in forecasting technology could be one of the most cost-effective ways to reduce heat-related deaths in the long run.

For residents, this means paying closer attention to weather forecasts—not just for the day’s high temperature, but for the accuracy of those predictions. If a forecast calls for 105°F but the actual temperature hits 110°F, that’s a sign that the models need improvement. And in a city where heat is already the deadliest weather-related hazard, those improvements can’t come soon enough.

But the implications of this research extend far beyond Phoenix. Cities like Las Vegas, Dallas, and even traditionally cooler metros like Chicago are all facing the reality of more frequent and intense heat waves. As climate change accelerates, the need for accurate forecasting will become a national priority. The fine news? The technology to make it happen is already within reach. The question is whether cities and policymakers will prioritize it.

If This Affects You in Phoenix: Here’s Who You Need to Recognize

Given my background in covering the intersection of climate science, public health, and urban policy, I’ve seen firsthand how communities can adapt to extreme heat. If you’re a Phoenix resident—or if you live in another city where heat is becoming a growing threat—here are three types of local professionals who can aid you stay safe and informed:

Certified Heat-Health Specialists

These are public health professionals trained in the specific risks of extreme heat. They work with local governments to develop heat action plans, conduct vulnerability assessments, and educate the public. When hiring one, look for:

• Certification from organizations like the CDC’s Climate and Health Program or the American Public Health Association.
• Experience working with local health departments or nonprofits focused on heat mitigation.
• A track record of community engagement, particularly in high-risk neighborhoods like South Phoenix or Maryvale.

Urban Climate Scientists

These researchers study how cities amplify or mitigate heat, often through initiatives like green infrastructure or reflective pavement. They can help homeowners, businesses, and city planners design heat-resilient spaces. When seeking one out, prioritize:

• Affiliation with local institutions like Arizona State University’s School of Sustainability or the School of Earth and Space Exploration.
• Experience with urban heat island mapping, which identifies the hottest parts of the city.
• Publications or projects focused on Phoenix or similar desert climates.

Emergency Preparedness Consultants

These experts help individuals, businesses, and government agencies plan for extreme weather events. They can assess your home’s heat resilience, develop emergency response plans, or even train staff on heat safety protocols. Key criteria to look for:

• Certification from FEMA’s Emergency Management Institute or the American Red Cross.
• Experience with heat-specific preparedness, not just general emergency planning.
• Familiarity with local resources, such as Phoenix’s cooling centers or the Heat Relief Network.

Each of these professionals plays a unique role in helping Phoenix adapt to a hotter future. Whether you’re a homeowner looking to weatherize your property, a business owner concerned about employee safety, or a policymaker shaping the city’s heat response, connecting with the right experts can make all the difference.

Ready to find trusted professionals? Browse our complete directory of top-rated science and technology, climate change, and weather experts in the Phoenix area today.