Why Europe’s Cities Are Getting Hotter—And Sicker

The City Heat That Won’t Go Away

Step outside after sunset in the middle of a European summer, and you might expect some relief. But in cities like Milan, Vienna, or Zurich, the night often brings no break from the heat.

Instead, the streets still radiate warmth. Brick walls, asphalt roads, and concrete courtyards soak up the sun all day—then release it slowly, like massive thermal batteries. You open a window hoping for a breeze, but it’s like sticking your head in an oven.

This isn't just annoying. It's becoming a real problem.

Urban Europe is heating up—and not just during the day. Nights are growing warmer, and in many places, dangerously so. The rise of “tropical nights” and the way our cities are built are creating an environment that affects not only comfort but also health and daily function.

Tropical Nights Are on the Rise

Let’s be clear: a “tropical night” doesn’t mean palm trees and beach cocktails. It means your body doesn’t get a break from the heat—because the temperature doesn’t drop below 20 or even 25°C overnight.

In 2023, parts of Zurich recorded over ten tropical nights in a row. Paris, Rome, and Budapest have all seen record-breaking streaks in recent years. And it’s not just southern Europe anymore—central regions like Switzerland, Germany, and Austria are feeling it too.

Nights are warming faster than days across much of the continent. That’s especially alarming, because humans rely on cooler nights to rest, recover, and reset. Without them, our bodies stay in stress mode.

Climate researchers point to global warming as the driver, with European cities heating up faster than many other parts of the world. But it’s not just the planet—it’s also the pavement.

Cities Are Trapping the Heat

The real villain here? The way our cities are built.

Urban areas are full of materials like asphalt, concrete, and glass that absorb and hold heat. This phenomenon is called the urban heat island effect. During the day, these materials soak in solar energy. At night, they release it slowly, keeping city temperatures much higher than surrounding countryside.

Add to that narrow streets that trap warm air, building surfaces that radiate heat, and a serious lack of greenery—and you've got a recipe for round-the-clock heat stress.

Trees and green spaces act like natural air conditioners. But in many European cities, they've been paved over, squeezed out, or never planted to begin with. Some neighborhoods can be up to 5°C warmer than nearby parks or forests.

That difference might not seem huge on paper—but if you’re trying to sleep, recover from illness, or just not melt on your way to work, it’s massive.

What It Means for Public Health

This isn’t just about comfort anymore—it’s about health.

When cities can’t cool down, bodies can’t either. Hot nights disrupt sleep, and poor sleep leads to more than just grumpiness. It affects heart rate, blood pressure, mood regulation, and even immune function. Over time, it chips away at physical resilience—especially in older adults or those with chronic illnesses.

Heat-related illness doesn’t wait for the sun. Studies have linked high nighttime temperatures with increased hospital admissions for cardiovascular and respiratory issues. During prolonged heatwaves, the risk of stroke, heart attack, and even premature death rises.

Children and the elderly are the most vulnerable, but so are people living with long COVID, diabetes, or other chronic health conditions. The body needs a chance to reset. When it’s 28°C at 2:00 a.m., that chance disappears.

And the problem is worse in cities. The same infrastructure that makes cities vibrant and dense also makes them slow to cool. It’s a dangerous feedback loop—one we can’t afford to ignore.

Infrastructure and Inequality

Not everyone feels the heat the same way.

Top-floor flats. Thin walls. No insulation. No air conditioning. These are common features in older European buildings—and they turn entire homes into heat traps. In wealthier districts, residents might afford portable A/C units or weekend escapes. In working-class neighborhoods, families sweat it out.

Inequality is baked into the bricks.

Many of the most at-risk populations—seniors living alone, migrants, people in subsidized housing—are the least likely to have the means to cope. They’re more likely to live in dense, poorly ventilated areas, and less likely to have access to green spaces nearby.

City design plays a role here, too. Lack of trees, dark-colored rooftops, and tight clusters of buildings reduce airflow and amplify heat. It’s not just a matter of temperature—it’s a matter of who’s protected and who’s exposed.

 

What Needs to Change (Long Term)

The long-term fix isn’t just cooler air—it’s smarter cities.

To adapt to rising temperatures, European cities need to rethink how they’re built and rebuilt. That means planting more trees—not just in parks, but along streets and around buildings. It means using reflective materials for rooftops and pavements that don’t absorb so much heat. It means creating more shaded public spaces, better ventilation in housing, and expanding green roofs that literally grow cooler air.

Urban planners are starting to take heat seriously, but the pace is slow. The gap between climate science and zoning policy is wide. In the meantime, people are living in environments that weren’t designed to handle today’s summers.

And the heat isn’t waiting.

And What Can Individuals Do Right Now?

We can’t redesign cities overnight—but we can find practical ways to stay safer in the heat today.

That’s where personal cooling gear comes in. For people who can’t stay in air-conditioned buildings—or who don’t have access to one at all—there’s a growing interest in wearable solutions that provide relief during the hottest parts of the day.

One of those comes from Duracool, a Swiss-made cooling vest developed by the tech spin-off Nahtlos AG in St. Gallen. Unlike traditional tech gear, it doesn’t run on batteries or require electricity. It uses evaporative cooling: fill it with water, seal it, and wear it. The fabric does the work—lowering your body temperature by up to 5°C for several hours.

It’s not meant for sleep, but it’s ideal for daytime challenges:

• Walking in the sun
• Caring for children or elderly relatives
• Working in hot conditions
• Simply staying functional during extreme heat

In a way, it's like carrying your own air conditioner—quiet, light, and sustainable.

Conclusion: Cities Must Adapt—But People Can Act Today

Europe’s cities are getting hotter. Nights offer less and less relief. And while systemic change is essential, it won’t happen overnight.

Until our streets get greener and our buildings get smarter, people still need ways to manage the heat. Personal cooling gear like Duracool offers one small but meaningful step: staying cool without power, emissions, or expensive installations.

Because sometimes, surviving the heat isn’t about changing the climate—it’s about changing how you respond to it.

Learn more about Duracool at duracoolwear.com