Eastern Heatwave 2025: Which US cities are worst hit? How concerned should Europe be?

A runner jogs along George Washington Memorial Parkway at sunrise on Tuesday in Arlington, Virginia.

🌡️ 1. Heat wave hits: coverage and hot and cold double impact

In late June 2025, a strong "heat dome" high-pressure system covered the central and eastern United States, affecting at least 150 million to 200 million people. This heat wave not only caused soaring temperatures during the day, but also was accompanied by sweltering nights, making it difficult for the human body to rest and recover.

Meteorological agencies predict that many areas from the East Coast to the Midwest will continue to experience high temperatures and high humidity, with the heat index (feeling temperature) generally between 105°F–115°F (about 40°C to 46°C).

🏙️ 2. The "roasting" level of each city: a list of the major disaster-affected cities

The heat wave hit several hubs along the I‑95 commuter belt, including:

🚨 3. Crisis and response measures in cities

⚡ Grid and infrastructure stress

• New York power supplier Con Ed called for power rationing and local voltage reduction (8%) to prevent collapse;

• Amtrak and subways have reduced speeds or stopped operating as high temperatures have caused line deformation and insufficient cooling of trains.

🏥 Public Health Emergency Measures

• Many places have opened "cooling centers" for people to escape the heat;

• Increased hospital emergency visits due to dehydration and heat stroke;

• Special attention is paid to the elderly, outdoor workers and the homeless.

🌍 Environmental and logistics pressure

• The ground asphalt melts and the rails expand;

• Increased risk of regional wildfires and ozone pollution;

• The potential for damage to agricultural and forestry water sources and crops is significant.

⚠️ 4. Why should Europe care?

🔁 Extreme heat is no longer far away

Europe has recently experienced record-breaking high temperatures, and the disaster scenarios in North America represent a risk of replication in the future . Heat waves are more than just heat - they are a systemic stress test for urban systems, energy networks and public health.

📚 Coping strategies that can be used as reference

• Open cooling center

• Emergency power dispatch and voltage reduction measures

• Adjustments to public services (transportation, leisure, outdoor activities, etc.)
  These measures are of reference value for improving the resilience of European cities under extreme high temperatures.

🤝 Strengthening transatlantic climate cooperation

Climate change knows no borders, and the real-time pressure on the United States in responding to heat waves will help the two sides deepen exchanges in the areas of adaptation and mitigation, such as early warning systems and energy resilience planning.

📈 5. Interpretation of climate trends: How “abnormal” is this heat wave?

• Climate Central analysis : This event has increased the likelihood of extreme heat exposure to 174 million people by at least three times;

• Historic records : New York broke 100°F for only the fourth time in June, and Connecticut set a continuous record in June;

• Sweltering nighttime heat : Sustained nighttime high temperatures make “24-hour heat stress” possible, rather than a single-day heat wave.

✅ Conclusion: Heat waves are not “isolated events”, but a reflection of global climate pressure

This heat wave in the eastern United States shows:

• Extreme heat waves have gone from rare to the norm

• Infrastructure and public services face extreme climate challenges

• Greenhouse gas-driven climate change is happening simultaneously around the world

For Europe, monitoring, learning and collaboration on this transcontinental climate extreme is crucial. Investments in green infrastructure and community resilience should continue to be made in the future to prepare for the irreversible reality of high temperatures.